Benign or by Chance: A Case Report on Incidental Appendectomy Revealing a Neuroendocrine Tumor During Traumatic Exploratory Laparotomy.

Incidental appendectomies (IAs) are often performed in laparotomies to prevent future complications caused by the buildup of scar tissue. Although neoplastic findings are rare, all appendectomy specimens should be sent for histopathological analysis. We present the case of a 38-year-old man found to have an appendiceal neuroendocrine tumor (NET) after receiving an IA secondary to a traumatic rectal perforation requiring exploratory laparotomy. Well-differentiated NETs isolated to the appendix have an excellent prognosis. Appendectomies are considered curative for NETs smaller than 2 cm that have not metastasized beyond the appendix. Appendiceal NETs are capable of secreting vasoactive substances and, therefore, causing carcinoid syndrome. However, the progression to carcinoid syndrome generally coincides with metastasis to the liver, indicating a poor prognosis. While histopathological analysis of appendectomy specimens rarely yields atypical findings, this analysis is crucial to ensure that the proper treatment is selected based on tumor progression in an appendectomy specimen staining positive for somatotropin and chromogranin.

Transcription factor NF-κB in a basal metazoan, the sponge, has conserved and unique sequences, activities, and regulation.

Herein, we characterize transcription factor NF-κB from the demosponge Amphimedon queenslandica (Aq). Aq-NF-κB is most similar to NF-κB p100/p105 among vertebrate proteins, with an N-terminal DNA-binding domain, a C-terminal Ankyrin (ANK) repeat domain, and a DNA binding-site profile akin to human NF-κB proteins. Like mammalian NF-κB p100, C-terminal truncation allows nuclear translocation of Aq-NF-κB and increases its transcriptional activation activity. Expression of IκB kinases (IKKs) induces proteasome-dependent C-terminal processing of Aq-NF-κB in human cells, and processing requires C-terminal serines in Aq-NF-κB. Unlike NF-κB p100, C-terminal sequences of Aq-NF-κB do not inhibit its DNA-binding activity. Tissue of a black encrusting demosponge contains NF-κB site DNA-binding activity, as well as nuclear and processed NF-κB. Treatment of sponge tissue with LPS increases both DNA-binding activity and processing of NF-κB. A. queenslandica transcriptomes contain homologs to upstream NF-κB pathway components. This is first functional characterization of NF-κB in sponge, the most basal multicellular animal.