Abstract Background Guidelines recommend that all patients with upper gastrointestinal bleeding (UGIB) undergo endoscopy within 24 h. It is unclear whether a subgroup may benefit from an urgent intervention. We aimed to evaluate the influence of endoscopic hemostasis and urgent endoscopy on mortality in UGIB patients with high-risk stigmata (HRS). Methods Consecutive patients with suspected UGIB were enrolled in three Japanese hospitals with a policy to perform endoscopy within 24 h. The primary outcome was 30-day mortality. Endoscopic hemostasis and endoscopy timing (urgent, ≤6 h; early, >6 h) were evaluated in a regression model adjusting for age, systolic pressure, heart rate, hemoglobin, creatinine, and variceal bleeding in multivariate analysis. A propensity score of 1:1 matched sensitivity analysis was also performed. Results HRS were present in 886 of 1966 patients, and 35 of 886 (3.95%) patients perished. Median urgent-endoscopy time (n = 769) was 3.0 h (interquartile range [IQR], 2.0–4.0 h) and early endoscopy (n = 117) was 12.0 h (IQR, 8.5–19.0 h). Successful endoscopic hemostasis and urgent endoscopy were significantly associated with reduced mortality in multivariable analysis (odds ratio [OR], 0.22; 95% confidence interval [CI], 0.09–0.52; P = 0.0006, and OR, 0.37; 95% CI, 0.16–0.87; P = 0.023, respectively). In a propensity-score-matched analysis of 115 pairs, adjusted comparisons showed significantly lower mortality of urgent vs early endoscopy (2.61% vs 7.83%, P < 0.001). Conclusions A subgroup of UGIB patients, namely those harboring HRS, may benefit from endoscopic hemostasis and urgent endoscopy rather than early endoscopy in reducing mortality. Implementing triage scores that predict the presence of such lesions is important.
Abstract 857: ELF3 modulates mesenchymal to epithelial transition through regulation of CD44 variant isoform expression in pancreatic cancer cells
Abstract BACKGROUND: Epithelial to Mesenchymal Transition (EMT) and Mesenchymal to Epithelial Transition (MET) may participate in pancreatic ductal adenocarcinoma (PDAC) metastasis. CD44 proteins are cell membrane proteins which function as co-receptors regulating many cellular functions. Some reports have shown that isoform switching from CD44 variant form (CD44v) to CD44 standard form (CD44s) takes place during the EMT. (Brown et al., J. Clin. Invest, 2011, Yae et al., Nat Commun., 2012). The AIM of this study was to explore the regulation of CD44 isoform switching in PDAC cells. Methods: The expression levels of CD44v and CD44s in PDAC cell lines were assessed by immunohistochemistry and immunoblot analysis. PDAC cell lines were implanted into immunodeficiency mice and treated with sulfasarazine for 14 days. Sulfasarazine, which inhibits glutamate-cysteine transport, reduces CD44v-dependent cell growth. CD44v or CD44s positive cells were isolated using flow cytometry and induced to undergo the EMT by TGF-β treatment (7.5ng/mL) for 72 hours. A doxycycline inducible system was employed to overexpress Slug, which promotes the EMT phenotype. To induce MET, the cells were released from TGF-β treatment and cultured for an additional 72 hours. E74-like ETS Transcription Factor 3 (ELF3) expression was knocked-down by siRNA transfection. RESULTS: Immunohistochemistry analysis revealed that CD44v protein is expressed specifically by PDAC with ductal structures within the complex tumor environment of these cancers. However, in contrast, CD44v expression was not observed in solitary infiltrating cancer cells. PANC-1, AsPC-1 and SUIT-2 PDAC cell lines expressed both CD44v and CD44s isoforms. Tumor mass in implanted PANC-1, AsPC-1 and SUIT-2 cells were reduced 69%, 50% and 36% respectively by sulfasarazine treatment following 2 weeks of therapy. However, CD44v null HPAC cells were resistant to sulfasarazine therapy following implantation. E-cadherin was expressed in CD44v positive cells but not in CD44s positive cells, and both CD44v and E-cadherin protein were reduced by TGF-β treatment. Slug over expressed cells were resistant to sulfasarazine treatment compared to non-Slug-induced cells. Removal of TGF-β restored both CD44v and E-cadherin expression levels which consistently occurs with MET. However, restoration of CD44v expression was diminished when ELF3 expression was reduced by siRNA transfection. CONCLUSION: The isoform switching between CD44v and CD44s was reversible. The expression of CD44v isoform appears to be controlled by ELF3 during MET. Citation Format: Ayano Kabashima-Niibe, Hiromasa Takaishi, Takanori Kanai, Hideyuki Saya, Gregory J. Gores, Hajime Higuchi. ELF3 modulates mesenchymal to epithelial transition through regulation of CD44 variant isoform expression in pancreatic cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 857. doi:10.1158/1538-7445.AM2017-857
Blockade of B7-H1 Suppresses the Development of Chronic Intestinal Inflammation
Abstract A newly identified costimulatory molecule, programmed death-1 (PD-1), provides a negative signal that is essential for immune homeostasis. However, it has been suggested that its ligands, B7-H1 (PD-L1) and B7-dendritic cells (B7-DC; PD-L2), could also costimulate T cell proliferation and cytokine secretion. Here we demonstrate the involvement of PD-1/B7-H1 and B7-DC interaction in the development of colitis. We first examined the expression profiles of PD-1 and its ligands in both human inflammatory bowel disease and a murine chronic colitis model induced by adoptive transfer of CD4+CD45RBhigh T cells to SCID mice. Second, we assessed the therapeutic potential of neutralizing anti-B7-H1 and/or B7-DC mAbs using this colitis model. We found significantly increased expression of PD-1 on T cells and of B7-H1 on T, B, and macrophage/DCs in inflamed colon from both inflammatory bowel disease patients and colitic mice. Unexpectedly, the administration of anti-B7-H1, but not anti-B7-DC, mAb after transfer of CD4+CD45RBhigh T cells suppressed wasting disease with colitis, abrogated leukocyte infiltration, and reduced the production of IFN-γ, IL-2, and TNF-α, but not IL-4 or IL-10, by lamina propria CD4+ T cells. These data suggest that the interaction of PD-1/B7-H1, but not PD-1/B7-DC, might be involved in intestinal mucosal inflammation and also show a possible role of interaction between B7-H1 and an as yet unidentified receptor for B7-H1 in inducing T cell activation.