The IGF-II/mannose-6 phosphate receptor (IGF-II/M6PR) interacts with multiple tumor growth factors, including IGF-II and latent TGFbeta1. The IGF-II/M6PR has been proposed to be a tumor growth suppressor, a hypothesis supported by our previous finding that decreased IGF-II/M6PR expression enhances tumor growth. In this study, we further demonstrate that IGF-II/M6PR overexpression, resulting from cDNA transfection of JEG-3 choriocarcinoma cells, leads to a decreased cellular growth rate in vitro and decreased tumor growth in nude mice. Examination of several IGF-II/M6PR ligands in receptor-overexpressing cells showed no change in endogenous IGF-II or secretion of procathepsins D and L but an increase in latent TGFbeta1 secretion and activation. Cells transfected with cDNA for a truncated, soluble form of the receptor, previously shown to inhibit IGF-II-stimulated DNA synthesis, displayed a very slow growth rate in vitro and in nude mice but showed no alteration in TGFbeta1 levels. This suggests that, in IGFII/M6PR-transfected cells, increased levels of soluble IGF-II/M6PR may play a role in growth inhibition. Overall, the findings in this study are consistent with the hypothesis that the IGF-II/M6PR suppresses tumor growth.

Whereas dexamethasone non-specifically inhibits numerous mediators involved in inflammation and the immune response, roflumilast selectively inhibits a subset of pro-inflammatory cytokines and growth factors. These mediators and/or the cells that produce them may have critical roles in the pathogenesis of the lesions of chronic asthma.

The 46.4-kb nucleotide sequence of pSK41, a prototypical multiresistance plasmid from Staphylococcus aureus, has been determined, representing the first completely sequenced conjugative plasmid from a gram-positive organism. Analysis of the sequence has enabled the identification of the probable replication, maintenance, and transfer functions of the plasmid and has provided insights into the evolution of a clinically significant group of plasmids. The basis of deletions commonly associated with pSK41 family plasmids has been investigated, as has the observed insertion site specificity of Tn552-like β-lactamase transposons within them. Several of the resistance determinants carried by pSK41-like plasmids were found to be located on up to four smaller cointegrated plasmids. pSK41 and related plasmids appear to represent a consolidation of antimicrobial resistance functions, collected by a preexisting conjugative plasmid via transposon insertion and IS257-mediated cointegrative capture of other plasmids.

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Matrix metalloproteinase (MMP) overexpression has been implicated in the pathogenesis of colorectal carcinoma (CRC). Accumulating evidence suggests that MMP promoter single nucleotide polymorphisms (SNPs) effecting gene transcription are associated with enhanced susceptibility for the development of malignant disease, increased tumour invasiveness and poor patient survival. The aim of the current investigation was to determine whether such associations exist in a large CRC patient/control study population. Using an allelic discrimination real-time polymerase chain reaction, polymorphisms in the MMP-1, MMP-2 and MMP-3 gene promoters (À1607, À1306, and À1612 bp, respectively) were assessed in normal blood mononuclear cells from patients with CRC (n ¼ 503) and control subjects (n ¼ 471). Genotypes corresponding to each MMP SNP were correlated with tumour characteristics and clinical outcome. The frequency of each genotype was not statistically different between patients and control subjects and no significant differences were noted between the genotypes and tumour characteristics for the three MMP SNPs. CRC patients with the 2G/2G genotype for the MMP-1 SNP had significantly better 5-year survival compared to patients with a 1G allele (Po0.05). Our results demonstrate that CRC patients with a 2G/2G genotype in the MMP-1 gene promoter SNP have a favourable prognosis. Although our results were unexpected, given that this genotype is associated with enhanced MMP-1 transcriptional activity, they are consistent with recent data highlighting the anti-tumorigenic properties of MMPs.

Purpose: Advanced stage MOC have poor chemotherapy response and prognosis and lack biomarkers to aid Stage I adjuvant treatment. Differentiating primary mucinous ovarian carcinoma (MOC) from gastrointestinal (GI) metastases to the ovary is also challenging due to phenotypic similarities. Clinicopathological and gene expression data were analysed to identify prognostic and diagnostic features. Experimental Design: Discovery analyses selected 19 genes with prognostic/diagnostic potential. Validation was performed through the Ovarian Tumor Tissue Analysis consortium and GI cancer biobanks comprising 604 patients with MOC (n=333), mucinous borderline ovarian tumors (MBOT, n=151), upper GI (n=65), and lower GI tumors (n=55). Results: Infiltrative pattern of invasion was associated with decreased overall survival (OS) within 2-years from diagnosis, compared with expansile pattern in Stage I MOC (hazard ratio HR 2.77 (1.04-7.41, p=0.042). Increased expression of THBS2 and TAGLN were associated with shorter OS in MOC patients, (HR 1.25 (95% CI 1.04-1.51, p=0.016)) and (1.21 (1.01-1.45, p=0.043)) respectively. ERBB2 (HER2)-amplification or high mRNA expression was evident in 64/243 (26%) of MOCs, but only 8/243 (3%) were also infiltrative (4/39, 10%) or Stage III/IV (4/31, 13%). Conclusions: An infiltrative growth pattern infers poor prognosis within 2-years from diagnosis and may help select Stage I patients for adjuvant therapy. High expression of THBS2 and TAGLN in MOC confer an adverse prognosis and is upregulated in the infiltrative subtype which warrants further investigation. Anti-HER2 therapy should be investigated in a subset of patients. MOC samples clustered with upper GI, yet markers to differentiate these entities remain elusive, suggesting similar underlying biology and shared treatment strategies.

Tryptases are serine proteases that are thought to be uniquely and proteolytically active as tetramers. Crystallographic studies reveal that the active tetramer is a flat ring structure composed of four monomers, with their active sites arranged around a narrow central pore. This model explains why many of the preferred substrates of tryptase are short peptides; however, it does not explain how tryptase cleaves large protein substrates such as fibronectin, although a number of studies have reported in vitro mechanisms for generating active monomers that could digest larger substrates. Here we suggest that alternate mRNA splicing of human tryptase genes generates active tryptase monomers (or dimers). We have identified a conserved pattern of alternate splicing in four tryptase alleles (␣II, ␤I, ␤III, and ␦I), representing three distinct tryptase gene loci. When compared with their full-length counterparts, the splice variants use an alternate acceptor site within exon 4. This results in the deletion of 27 nucleotides within the central coding sequence and 9 amino acids from the translated protein product. Although modeling suggests that the deletion can be easily accommodated by the enzymes structurally, it is predicted to alter the specificity by enlarging the S1 or S2 binding pocket and results in the complete loss of the "47 loop," reported to be critical for the formation of tetramers. Although active monomers can be generated in vitro using a range of artificial conditions, we suggest that alternate splicing is the in vivo mechanism used to generate active tryptase that can cleave large protein substrates.

Tubo-ovarian high-grade serous carcinomas (HGSC) are highly proliferative neoplasms that generally respond well to platinum/taxane chemotherapy. We recently identified minichromosome maintenance complex component 3 (MCM3), which is involved in the initiation of DNA replication and proliferation, as a favorable prognostic marker in HGSC. Our objective was to further validate whether MCM3 mRNA expression and possibly MCM3 protein levels are associated with survival in patients with HGSC. MCM3 mRNA expression was measured using NanoString expression profiling on formalin-fixed and paraffin-embedded tissue (N=2355 HGSC) and MCM3 protein expression was assessed by immunohistochemistry (N=522 HGSC) and compared with Ki-67. Kaplan-Meier curves and the Cox proportional hazards model were used to estimate associations with survival. Among chemotherapy-naïve HGSC, higher MCM3 mRNA expression (one standard deviation increase in the score) was associated with longer overall survival (HR=0.87, 95% CI 0.81-0.92, p<0.0001, N=1840) in multivariable analysis. MCM3 mRNA expression was highest in the HGSC C5.PRO molecular subtype, although no interaction was observed between MCM3, survival and molecular subtypes. MCM3 and Ki-67 protein levels were significantly lower after exposure to neoadjuvant chemotherapy compared to chemotherapy-naïve tumors: 37.0% versus 46.4% and 22.9% versus 34.2%, respectively. Among chemotherapy-naïve HGSC, high MCM3 protein levels were also associated with significantly longer disease-specific survival (HR=0.52, 95% CI 0.36-0.74, p=0.0003, N=392) compared to cases with low MCM3 protein levels in multivariable analysis. MCM3 immunohistochemistry is a promising surrogate marker of proliferation in HGSC.