Risk factors and inflammatory markers in pouchitis

Individuals who do not respond to medical therapy for ulcerative colitis (UC) often undergo proctocolectomy followed by ileal-pouch anal anastomosis (IPAA) in hopes of resolving symptoms associated with UC. Inflammation of the ileal pouch, better known as pouchitis, is the most common complication of the IPAA procedure. The causes and development of pouchitis is not well understood. To better understand pathogenesis of pouchitis, pouch aspirates of patients having undergone IPAA were quantitatively analyzed for fecal IL-8, IL-17, and IL-23 levels. According to published literature IL-8 has been linked to pouchitis whereas IL-17 and IL-23 are associated with intestinal inflammation. The study had 80 participants, 33 patients diagnosed with Crohn's Disease (CD) of the pouch, 19 patients diagnosed with pouchitis, and 28 diagnosed with having normal pouches. Patient characteristics and histopathological findings for all patients were noted and statistically compared in addition to fecal cytokine levels. This study supported previous literature that IL-8 production was associated with pouch inflammation. However, IL-17 and IL-23 levels in both CD of the pouch and pouchitis were not significantly different to the levels noted in normal pouch.^

Killing of human melanoma cells induced by activation of class I interferon-regulated signaling pathways via MDA-7/IL-24.

Restoration of the tumor-suppression function by gene transfer of the melanoma differentiation-associated gene 7 (MDA7)/interleukin 24 (IL-24) successfully induces apoptosis in melanoma tumors in vivo. To address the molecular mechanisms involved, we previously revealed that MDA7/IL-24 treatment of melanoma cells down-regulates interferon regulatory factor (IRF)-1 expression and concomitantly up-regulates IRF-2 expression, which competes with the activity of IRF-1 and reverses the induction of IRF-1-regulated inducible nitric oxide synthase (iNOS). Interferons (IFNs) influence melanoma cell survival by modulating apoptosis. A class I IFN (IFN-alpha) has been approved for the treatment of advanced melanoma with some limited success. A class II IFN (IFN-gamma), on the other hand, supports melanoma cell survival, possibly through constitutive activation of iNOS expression. We therefore conducted this study to explore the molecular pathways of MDA7/IL-24 regulation of apoptosis via the intracellular induction of IFNs in melanoma. We hypothesized that the restoration of the MDA7/IL-24 axis leads to upregulation of class I IFNs and induction of the apoptotic cascade. We found that MDA7/IL-24 induces the secretion of endogenous IFN-beta, another class I IFN, leading to the arrest of melanoma cell growth and apoptosis. We also identified a series of apoptotic markers that play a role in this pathway, including the regulation of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and Fas-FasL. In summary, we described a novel pathway of MDA7/IL-24 regulation of apoptosis in melanoma tumors via endogenous IFN-beta induction followed by IRF regulation and TRAIL/FasL system activation.