A40 INTESTINAL EPITHELIAL NCOR1 TARGETS TRYPTOPHAN METABOLISM AND PROTECTS AGAINST EXPERIMENTAL COLITIS

Background

The nuclear co-repressor NCOR1 is a central protein that orchestrates the assembly of a large transcriptional repression complex. NCOR1 controls activation of macrophages by repressing a large variety of pro-inflammatory genes.

Aims

We aimed to investigate the role of intestinal epithelial NCOR1 during experimental colitis.

Methods

Conditional deletion of Ncor1 in the whole intestinal epithelium was achieved by crossing Villin-Cre and Ncor1loxP/loxP C57BL/6 mouse models. A gene profiling analysis in the colon of non-diseased NCOR1ΔIEC and control mice was performed. NCOR1ΔIEC and control littermate mice were treated with dextran sulfate sodium (DSS) in drinking water.

Results

DSS-induced colitis in NCOR1ΔIEC mice was more severe than control mice according to survival as well as clinical observations. A statistical analysis predicted 85 unique and mapped transcripts being significantly modulated between NCOR1ΔIEC and control mice. An Ingenuity Pathway Analysis from these predicted target genes identified gastrointestinal disease (79 transcripts) as top disease and biofunction. Analysis of enriched targets in specific canonical pathways predicted an increase in the tryptophan degradation pathway (P = 3.2E-02), a pathway recently demonstrated to be strongly relevant to inflammatory bowel disease severity. Indoleamine-pyrrole 2,3-dioxygenase (IDO1), that catalyzes the first and rate-limiting step of tryptophan oxidation, was induced more than 7 times in the colon of NCOR1ΔIEC mice. Induction of Ido1 was also confirmed in cultured ex vivo colon organoids deleted for Ncor1.

Conclusions

Our results highlight the critical role of NCOR1 to maintain intestinal inflammatory homeostasis during experimental colitis and uncover a novel function for NCOR1 in the regulation of Ido1 expression and potentially tryptophan metabolism.

Funding Agencies

CIHR

[The significance of PSA density as predictive factor in Afro-Caribbean patients eligible for active surveillance by the French protocol criteria]

OBJECTIVES

Study the interest of addition of PSA density (PSAD), to the selection criteria of the French protocol for inclusion patients Afro-Caribbean on active surveillance prostate cancer.

METHODS

A retrospective analysis of 1505 patients who had, in turn, a radical prostatectomy for cancer between 2000 and 2012, in a single reference center. One hundred and forty-one patients was eligible, at the time of their diagnosis, for active surveillance by the criteria of the French protocol. This population was divided into 2 groups according to the histological analysis of the prostatectomy specimen confirmed indolent cancer or overturned. The median PSAD of each group was calculated to be compared. Secondarily, the most discriminating PSAD was investigated by the method of ROC after constitution tables intrinsic validity in this population. This threshold has secondary conducting a comparative analysis of the underestimation of cancer in terms of aggressiveness and/or extension between patients selected according to the criteria of the French protocol and "on-selected" patients according to these criteria and their PSAD.

RESULTS

Of the 141 patients identified for analysis, histological examination of the prostatectomy specimen has to show that 42 patients (29.7 %) were actually more aggressive cancer (20.6 % of Gleason ≥ 7), wider (4.2 % ≥ pT3) or larger and more aggressive (4.9 %) than foreshadowed criteria French protocol. The median PSAD these 42 patients were significantly higher than the median PSAD patients correctly estimated (0.18 vs. 0.14, p-value=0.046). The application of the most discriminating threshold: 0.15 ng/ml/cm(3) in this population allowed to significantly improve the selection of candidates of the 79 "on-selected" patients, six (20.2 %) were actually more aggressive cancer (13.9 % of Gleason ≥ 7), wider (2.5 % ≥ pT3) or larger and more aggressive (3.8 %).

CONCLUSION

The criteria for the French protocol for active surveillance, applied to the Caribbean population underestimate 29 % of non-latent cancers. Adjuvants criteria that must be inexpensive, sensitive and specific seem necessary in this population. A PSAD<0.15 ng/ml/cm(3) could be one of these criteria.

Acute ischemic stroke: imaging-guided tenecteplase treatment in an extended time window

BACKGROUND

Tenecteplase is a modified tissue plasminogen activator with a longer half-life and higher fibrin specificity than alteplase.

METHODS

We conducted a prospective, nonrandomized, pilot study of 0.1 mg/kg IV tenecteplase given 3 to 6 hours after ischemic stroke onset. For a control group, we used patients contemporaneously treated with sub-3-hour 0.9 mg/kg IV alteplase following standard selection criteria. All patients underwent pretreatment and 24-hour perfusion/angiographic imaging with CT or MRI. Eligibility criteria for tenecteplase (but not alteplase) treatment included a perfusion lesion at least 20% greater than the infarct core, with an associated vessel occlusion. Primary outcomes, assessed blind to treatment group, were reperfusion (reduction in baseline-24-hour mean transit time lesion) and major vessel recanalization.

RESULTS

Fifteen patients received tenecteplase, and 35 patients received alteplase. The tenecteplase group had greater reperfusion (mean 74% vs 44% in the alteplase group, p = 0.01) and major vessel recanalization (10/15 tenecteplase vs 7/29 alteplase, p = 0.01). Despite later time to treatment, more tenecteplase patients (10/15 vs 7/35 alteplase, p = 0.001) had major neurologic improvement at 24 hours (NIH Stroke Scale reduction > or = 8). Four of the alteplase patients and none of the tenecteplase patients had parenchymal hematoma at 24 hours.

CONCLUSIONS

Tenecteplase 0.1 mg/kg, using advanced imaging guidance in an extended time window, may have significant biologic efficacy in acute ischemic stroke. The imaging selection differences between the tenecteplase and alteplase groups prevent a conclusive efficacy comparison. Nonetheless, these results lend support for randomized trials comparing tenecteplase with alteplase, preferably incorporating penumbral/angiographic imaging selection.