Survival by anatomic site, histologic type, and tumor stage in stomach and esophageal cancer patients from the U.S. SEER Cancer Registry

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Background: Data on the association of tumor characteristics and survival for stomach cancer (SC) and esophageal cancer (EC) patients (pts) are limited. The objective of this study was to describe survival in United States. SC and EC pts by anatomic site, histologic type, and tumor stage.

Methods: SC and EC pts were identified in the Surveillance, Epidemiology and End Results (SEER) Cancer Registry. SC was classified by anatomic site (cardia and non-cardia/other) and histologic type (intestinal, diffuse, other per Lauren criteria). EC was classified into anatomic site (middle/upper third, abdominal/lower third, overlapping lesions, NOS) and histologic type (adenocarcinoma (AC), squamous cell carcinoma (SQ), other). Frequency distribution and median survival were examined in these subgroups.

Results: From 2004-2006, >15,500 SC and > 9,800 EC cases were diagnosed. SC: (29% cardia) and (24% diffuse, 66% intestinal, 10% other). Compared with non-cardia/other pts, cardia pts tended to be male (77% vs 56%), white (88% vs 66%), intestinal type (77% vs 61%) and present with earlier stage disease (stage I-IIIa: 48% vs 42%). With the exception of stage I/II pts, survival was longer in cardia than non-cardia/other pts. The difference was most striking in stage IIIb/IV pts (7 months (mos) cardia vs 4 mos non-cardia/other). Compared to intestinal type, diffuse type tended to be younger (median age: 64 vs 72 yrs), more female (49% vs 34%), and present with more stage IIIb/IV disease (50% vs 39%). No difference in survival by histologic type was observed when accounting for stage. EC: (26% middle/upper, 58% lower, 5% overlapping, 11% NOS) and (57% AC, 34% SQ, 9% other). Among pts with AC histology 78% occurred in the lower third; in SQ most occurred in upper/middle third (56%). Compared to SQ, AC tended to be male (85% vs 63%), white (95% vs 67%), and present with stage IV disease (34% vs 25%). For all stages combined, survival was longer for AC pts (11 mos AC, 9 mos SQ, 4 mos other). This difference was most apparent among early stage (I-III) pts.

Conclusions: Survival in SC and EC was associated with staging, anatomic and histologic subtypes. Quantifying this provides insights for the design and interpretation of clinical development programs.

[Table: see text]

Novel peptide-dendrimer conjugates as drug carriers for targeting nonsmall cell lung cancer

Phage display technology has been demonstrated to be a powerful tool for screening useful ligands that are capable of specifically binding to biomarkers on the surface of tumor cells. The ligands found by this technique, such as peptides, have been successfully applied in the fields of early cancer diagnostics and chemotherapy. In this study, a novel nonsmall cell lung cancer-targeting peptide (LCTP, sequence RCPLSHSLICY) was screened in vivo using a Ph.D.-C7C(™) phage display library. In order to develop a universal tumor-targeting drug carrier, the LCTP and fluorescence-labeled molecule (FITC) were conjugated to an acetylated polyamidoamine (PAMAM) dendrimer of generation 4 (G4) to form a PAMAM-Ac-FITC-LCTP conjugate. The performance of the conjugate was first tested in vitro. In vitro results of cell experiments analyzed by flow cytometry and inverted fluorescence microscopy indicated that PAMAM-Ac-FITC-LCTP was enriched more in NCI-H460 cells than in 293T cells, and cellular uptake was both time- and dose-dependent. The tissue distribution of the conjugate in athymic mice with lung cancer xenografts was also investigated to test the targeting efficiency of PAMAM-Ac-FITC-LCTP in vivo. The results showed that LCTP can effectively facilitate the targeting of PAMAM-Ac-FITC-LCTP to nonsmall cell lung cancer cells and tumors. These results suggest that the LCTP-conjugated PAMAM dendrimer might be a promising drug carrier for targeted cancer diagnosis and treatment.

Immunotherapy of melanoma by GPI-anchored IL-21 tumour vaccine involves down-regulating regulatory T cells in mouse model

In this study, we developed a tumour cell vaccine expressing a glycosylphosphatidylinositol (GPI)-anchored IL-21 to test the effect of immunotherapy of melanoma in mouse model. The results indicated that the tumour vaccine was functional, exhibiting delayed tumour growth and prolonging longevity of tumour bearing mice. The immunotherapeutic effect was associated with decreasing the numbers of CD4(+) CD25(+) Foxp3(+) Treg (Tregs) cells, increasing IFN-γ level and promoting lymphocyte-infiltration in tumour tissues. Overall, our data demonstrate that the GPI-anchored IL-21 tumour vaccine regulates immune responses at least in part by down-regulating Tregs and reveals enhanced efficacy of tumour vaccine therapy of melanoma.

Adsorption and function of recombinant Factor VIII at the air-water interface in the presence of Tween 80

The air-water surface tension kinetic and steady state behavior exhibited by a recombinant Factor VIII were recorded in the presence of the surfactant Tween 80. The rate of surface tension decrease was determined to be greater for rFVIII-Tween mixtures than for Tween acting alone, at all Tween concentrations studied (8-108 ppm). In addition, steady state interfacial behavior was determined to be governed entirely by surfactant adsorption in mixtures with Tween concentrations greater than or equal to about 18 ppm. The formation of aggregates, tertiary structure change, and biological activity of rFVIII in agitated as well as unagitated samples were monitored using turbidity measurements, intrinsic fluorescence spectroscopy, and the activated partial thromboplastin time, respectively. The results are consistent with two mechanisms characterizing the surfactant-mediated stabilization of rFVIII: the rapid, preferential adsorption of Tween molecules relative to rFVIII molecules at the air-water interface, and Tween association with rFVIII in solution to provide a steric barrier to aggregation. While both mechanisms are relevant in the presence of an interface, evidence recorded here suggests that the preferential adsorption of Tween at the interface is the major stabilization mechanism while the effectiveness of Tween association with rFVIII is compromised in agitated samples.

Methionine oxidation in human IgG2 Fc decreases binding affinities to protein A and FcRn

Susceptibility of methionine residues to oxidation is a significant issue of protein therapeutics. Methionine oxidation may limit the product's clinical efficacy or stability. We have studied kinetics of methionine oxidation in the Fc portion of the human IgG2 and its impact on the interaction with FcRn and Protein A. Our results confirm previously published observations for IgG1 that two analogous solvent-exposed methionine residues in IgG2, Met 252 and Met 428, oxidize more readily than the other methionine residue, Met 358, which is buried inside the Fc. Met 397, which is not present in IgG1 but in IgG2, oxidizes at similar rate as Met 358. Oxidation of two labile methionines, Met 252 and Met 428, weakens the binding of the intact antibody with Protein A and FcRn, two natural protein binding partners. Both of these binding partners share the same binding site on the Fc. Additionally, our results shows that Protein A may serve as a convenient and inexpensive surrogate for FcRn binding measurements.

Identification of tumor stem-like cells in a mouse myeloma cell line

We used colony formation assay in the soft agar media or the serum-free media, the methods of identifying BrdU-label-retaining cells and the SP cells as well as the tumorigenicity test in BALB/c mice, respectively, to analyze tumor stem like cells in the SP2/0 cell line. The results showed that a few SP2/0 cells were capable of forming colonies in the soft agar media, contained BrdU-label-immortal strand in the SP2/0 cell line. The SP2/0 cells in the serum-free media gained higher tumorigenicity in the BALB/c mice than the SP2/0 cells cultivated in the complete media did. Overall, only a few of the SP2/0 cells were found to possess the characteristics of tumor stem-like cells, such as high proliferative potency, more self-renewal and stronger tumorigenesis, or greater similarity to the tumor stem cells (TSCs) traits. The biology of tumor stem-like cells contributes to the identification of molecular targets important for future tumor therapy.

Role of Aggregatibacter actinomycetemcomitans in glutathione catabolism

INTRODUCTION

Our previous studies demonstrated that three enzymes, gamma-glutamyltransferase (GGT), cysteinylglycinase (CGase) and cystalysin, are required for the catabolism of glutathione to produce hydrogen sulfide (H(2)S) in Treponema denticola. In this study, we examined glutathione catabolism in Aggregatibacter actinomycetemcomitans.

METHODS

The GGT and CGase of A. actinomycetemcomitans were determined by biological methods and GGT was characterized using a molecular biological approach.

RESULTS

A. actinomycetemcomitans showed GGT and CGase activity, but could not produce H(2)S from glutathione. The addition of recombinant T. denticola cystalysin, an l-cysteine desulfhydrase, to whole cells of A. actinomycetemcomitans resulted in the production of H(2)S from glutathione. Subsequently, we cloned A. actinomycetemcomitans GGT gene (ggt) and overexpressed the 63 kDa GGT protein. The recombinant A. actinomycetemcomitans GGT was purified and identified. The K(cat)/K(m) of the recombinant GGT from N-gamma-l-glutamyl-4-nitroaniline as substrate was 31/microm/min. The activity of GGT was optimum at pH 6.9-7.1 and enhanced by thiol-containing compounds.

CONCLUSION

The results demonstrated that A. actinomycetemcomitans had GGT and CGase activities and that the GGT was characterized. The possible role of A. actinomycetemcomitans in glutathione metabolism and H(2)S production from oral bacteria was discussed.

Circulating natriuretic peptides in cats with heart disease

BACKGROUND

Circulating natriuretic peptide concentrations are increased in cats with myocardial dysfunction.

HYPOTHESIS

Serum N-terminal fragment of proatrial natriuretic peptide (NT-proANP) and NT-probrain natriuretic peptide (proBNP) concentrations may predict the presence of heart disease (HD) and congestive heart failure (CHF). A positive relationship is also predicted among natriuretic peptide (NP) concentrations, a noninvasive estimate of left ventricular filling pressure (E/E(a)), and an echocardiographic measure of left atrial (LA) size (LA/aortic diameter [Ao]).

METHODS

Serum NP concentrations were measured in 28 healthy control and 50 study cats using sandwich enzyme immunoassays. The study group comprised cats, with HD but no CHF (HD - CHF, n = 17) and cats with CHF (HD + CHF, n = 33). The relationship among NP concentrations, LA size, and E/E(a) was examined. The ability of NP to distinguish control from study cats, and HD - CHF from HD + CHF cats, was explored using receiver operator curve analysis.

RESULTS

NP concentrations were significantly lower in control than in study cats (P= .0001). The NT-proBNP concentrations were positively correlated with LA/Ao ratio (rho= 0.34; P= .02) and with E/E(a) ratio (rho= 0.68; P < .05). An NT-proBNP concentration of 49 fmol/mL gave a sensitivity and specificity of 100 and 89.3%, respectively, for correctly distinguishing 96.2% of control from study cats. Pairwise comparisons of the areas under the curve identified a statistically significant difference (P= .011) between NT-proANP and NT-proBNP to distinguish control from study cats. NT-proANP and NT-proBNP concentrations were significantly higher in HD + CHF cats than in HD - CHF cats (P= .0023 and .0001, respectively).

CONCLUSIONS

Serum concentrations of NT-proANP and particularly NT-proBNP were different in healthy control cats, asymptomatic cats with HD, and cats with CHF, suggesting that measurement of NP concentrations may prove clinically useful as an initial screening test for cats with suspected cardiac disease.

MAPK/ERK signalling mediates VEGF-induced bone marrow stem cell differentiation into endothelial cell

Multi-potent adult progenitor cells (MAPCs) differentiate into endothelial cells (ECs) in the presence of vascular endothelial growth factor (VEGF). The mechanism(s) of VEGF-induced differentiation of MAPCs to ECs are not yet known. We, therefore, examined the role of mitogen-activated protein kinase/extracellular signal-regulated kinase (p42/44-MAPK/ERK1/2) signalling in endothelial differentiation from bone marrow stem cells. We observed that VEGF stimulation of MAPCs for 14 days results in a significant expression of endothelial-specific gene and/or proteins including von Willebrand factor (vWF), vascular endothelial-cadherin (VE-cadherin), VEGF receptor-2 (VEGFR2), and CD31. Up-regulation of EC-specific markers was accompanied by a cobblestone morphology, expression of endothelial nitric oxide synthase (eNOS), and Dil-Ac-LDL uptake, typical for EC morphology and function. VEGF induced a sustained activation of p42 MAPK/ERK, but not that of p44 MAPK/ERK during the course of MAPCs differentiation in a time-dependent manner up to 14 days. VEGF-induced activation of p42 MAPK/ERK also led to the nuclear translocation of MAPK/ERK1/2. Incubation of MAPCs with MAPK/ERK1/2 phosphorylation inhibitor PD98059 blocked the sustained VEGF-induced MAPK/ERK1/2 phosphorylation as well as its nuclear translocation in the differentiating MAPCs. Inhibition of MAPK/ERK1/2 phosphorylation by PD98059 also blocked the expression of EC-specific genes in these cells and their differentiation to ECs. These data suggest that VEGF induces MAPC differentiation into EC via a. MAPK/ERK1/2 signalling pathway-mediated mechanism in vitro.

Oncolytic adenovirus-mediated shRNA against Apollon inhibits tumor cell growth and enhances antitumor effect of 5-fluorouracil

Apollon, a membrane-associated inhibitor of apoptosis protein, protects cells against apoptosis and is upregulated in certain tumor cells. In this study, the effects of Apollon protein knockdown by RNA interference on the growth of human HeLa, HT-1080 and MCF-7 cells in vitro and in vivo were investigated. An oncolytic adenovirus (ZD55) containing the RNA polymerase III-dependent U6 promoter to express short hairpin RNA (shRNA) directed against Apollon (ZD55-siApollon) was constructed. Our data show that ZD55-siApollon successfully exerts a gene knockdown effect and causes the inhibition of tumor cell growth both in culture and in athymic mice in vivo. Cell cycle analysis, 4',6-diamidino-2-phenylindole staining and western blot analysis reveal that ZD55-siApollon-mediated suppression of Apollon induces apoptosis. Intratumoral injection of ZD55-siApollon significantly inhibits tumor growth in HT-1080 xenograft mice. Furthermore, ZD55-siApollon enhances the antitumor effect of 5-fluorouracil, a chemotherapeutic agent. In conclusion, these results suggest that the depletion of Apollon by oncolytic adenovirus-shRNA delivery system provides a promising method for cancer therapy.

The Advanced Renal Cell Carcinoma Sorafenib (ARCCS) expanded access trial: Safety and efficacy in patients (pts) with prior bevacizumab (BEV) treatment

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Background: Sorafenib (SOR) is an oral multi-kinase inhibitor of tumor-cell angiogenesis and proliferation. Phase III (TARGETs) data have demonstrated prolonged progression-free survival in pts with advanced clear cell renal cell carcinoma (RCC) in whom prior therapy failed. Activity of SOR following treatment with BEV, an anti-vascular endothelial growth factor and antiangiogenic monoclonal antibody, has not been evaluated. Methods: A subset analysis was conducted to describe safety and efficacy in the SOR expanded access program in North America for pts receiving prior BEV. Inclusion criteria for this open-label, nonrandomized trial included advanced RCC; ineligibility for, or lack of access to, other SOR clinical trials; age =15 years; ECOG PS of 0–2; recovery from prior treatment; adequate prior treatment of brain metastases. Major exclusion criteria included life expectancy <2 months; active coronary artery disease, ischemia or hypertension; severe renal impairment requiring dialysis. Pts previously treated with BEV required =28 days from last dose, no =Grade 3 hemorrhagic episode during therapy, and no history of =Grade 2 hemorrhagic event 6 mos prior to BEV treatment. Results: Of the 2,488 pts in ARCCS valid for safety analysis, 289 pts had received prior BEV: 65% male with median age 61 yrs. Grade 3 and 4 toxicities occurring in >2% of prior BEV pts included hand-foot skin reaction 9.0%; fatigue 6.9%; hypertension 4.8%; dehydration, dyspnea, anorexia, and abdominal pain 3.1%; back pain, rash/desquamation, and mucositis 2.8%; pleural effusion and diarrhea 2.1%. Of the 195 BEV-pretreated pts evaluable for response, 152 (77.5%) had stable disease and 5 (2.5%) had confirmed partial responses (PR). There were 26 (13.3%) unconfirmed PRs reported according to RECIST, 4 of which missed a second scan due to US ARCCS enrollment ceasing upon FDA approval of SOR in 12/05. Conclusions: We observed activity of SOR following BEV therapy for advanced RCC. AEs in this subset were generally well tolerated and similar to those in the overall ARCCS population. Further investigation is warranted to elucidate mechanisms for response to SOR following prior antiangiogenic treatment.

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Upregulation of T-bet expression in peripheral blood mononuclear cells during Vogt-Koyanagi-Harada disease

AIM

To test the hypothesis that T-bet expression is altered in patients with Vogt-Koyanagi-Harada (VKH) disease.

METHODS

Peripheral blood was withdrawn from 16 VKH patients before and after immunosuppressive treatment and from 16 healthy individuals. IFN-gamma, IL-2, and IL-4 in the serum and the supernatants of peripheral blood mononuclear cells (PBMC) cultured with or without phytohaemagglutinin (PHA) were measured by ELISA. T-bet mRNA and protein expression in PBMC cultured with or without PHA was detected by RT-PCR and western blot, respectively.

RESULTS

The level of IFN-gamma, but not IL-2 and IL-4, was significantly higher in the supernatants of stimulated PBMC in patients than in controls. A significantly increased T-bet mRNA was found in VKH patients during an active uveitis episode, but not in quiescent patients, compared to controls. T-bet protein was detectable in VKH patients during an active uveitis episode, but not in quiescent patients nor in the healthy controls. Stimulation of PBMC with PHA resulted in a marked upregulation of T-bet mRNA and protein expression for both patients and controls with no significant difference between the two groups.

CONCLUSIONS

Upregulation of T-bet may be associated with the development of a Th1 mediated immune response in VKH disease.

Effects of androstenedione on long term potentiation in the rat dentate gyrus. Relevance for affective and degenerative diseases

We studied the effects of the androgenic hormone androstenedione, a 17-ketosteroid, on long term potentiation (LTP) in the dentate gyrus (DG) of intact, urethane anesthetized rats. Intravenous injection of 10mg of the hormone dissolved in Nutralipid produced a significant increase of the population spike (PS), but not of the excitatory post-synaptic potentials (EPSPs). The results are discussed in terms of the potential enhancement that androstenedione may have on some aspects of memory processes as reported for other androgenic steroids. Also noted are the plausible beneficial effects of the hormone on depression as well as in recovery following both central and peripheral neural injury.