Confocal Endomicroscopy Characteristics of Different Intraductal Papillary Mucinous Neoplasm Subtypes

Intraductal papillary mucinous neoplasms are classified into gastric, intestinal, pancreatobiliary, and oncocytic subtypes where morphology portends disease prognosis. The study aim was to demonstrate EUS-guided needle-based confocal laser endomicroscopy imaging features of intraductal papillary mucinous neoplasm subtypes. Four subjects, each with a specific intraductal papillary mucinous neoplasm subtype were enrolled. An EUS-guided needle-based confocal laser endomicroscopy miniprobe was utilized for image acquisition. The mean cyst size from the 4 subjects (2 females; mean age = 65.3±12 years) was 36.8±12 mm. All lesions demonstrated mural nodules and focal dilation of the main pancreatic duct. EUS-nCLE demonstrated characteristic finger-like papillae with inner vascular core for all subtypes. The image patterns of the papillae for the gastric, intestinal, and pancreatobiliary subtypes were similar. However, the papillae in the oncocytic subtype were thick and demonstrated a fine scale-like or honeycomb pattern with intraepithelial lumina correlating with histopathology. There was significant overlap in the needle-based confocal laser endomicroscopy findings for the different intraductal papillary mucinous neoplasm subtypes; however, the oncocytic subtype demonstrated distinct patterns. These findings need to be replicated in larger multicenter studies

Activation of JNK Signaling Mediates Amyloid-ß-Dependent Cell Death

Alzheimer's disease (AD) is an age related progressive neurodegenerative disorder. One of the reasons for Alzheimer's neuropathology is the generation of large aggregates of Aß42 that are toxic in nature and induce oxidative stress, aberrant signaling and many other cellular alterations that trigger neuronal cell death. However, the exact mechanisms leading to cell death are not clearly understood.We employed a Drosophila eye model of AD to study how Aß42 causes cell death. Misexpression of higher levels of Aß42 in the differentiating photoreceptors of fly retina rapidly induced aberrant cellular phenotypes and cell death. We found that blocking caspase-dependent cell death initially blocked cell death but did not lead to a significant rescue in the adult eye. However, blocking the levels of c-Jun NH(2)-terminal kinase (JNK) signaling pathway significantly rescued the neurodegeneration phenotype of Aß42 misexpression both in eye imaginal disc as well as the adult eye. Misexpression of Aß42 induced transcriptional upregulation of puckered (puc), a downstream target and functional read out of JNK signaling. Moreover, a three-fold increase in phospho-Jun (activated Jun) protein levels was seen in Aß42 retina as compared to the wild-type retina. When we blocked both caspases and JNK signaling simultaneously in the fly retina, the rescue of the neurodegenerative phenotype is comparable to that caused by blocking JNK signaling pathway alone.Our data suggests that (i) accumulation of Aß42 plaques induces JNK signaling in neurons and (ii) induction of JNK contributes to Aß42 mediated cell death. Therefore, inappropriate JNK activation may indeed be relevant to the AD neuropathology, thus making JNK a key target for AD therapies

An appraisal of pancreatic cyst fluid molecular markers

Pancreatic malignancy is the third leading cause of cancer related death in the United States with limited viable screening options. By the end of this decade, cancers are poised to become the leading cause of death with pancreatic cancer projected to be the second leading cause of cancer related mortality. Pancreatic cystic lesions (PCLs) are found in approximately 5%–14% of patients due to the increased utilization of cross-sectional imaging, with approximately 8%–10% of pancreatic cancers originating as PCLs. Current screening guidelines have shown discrepancies between morphologic characteristics of PCLs and identifying advanced pancreatic disease. Molecular analysis has emerged as a novel technology to aid in adequate diagnosis and management decisions of PCLs. Mucinous cysts including intraductal papillary mucinous neoplasms (IPMNs) or mucinous cystic neoplasms have similar oncogenic mutations including KRAS, TP53, SMAD4, PIK3CA, PTEN, or CKDN2A, while GNAS and RNF43 mutations are specific only to IPMNs. Serous cystadenomas have been associated with a loss of tumor suppressor gene VHL, while solid-psuedopapillary neoplasms have an oncogenic mutation CTNNB1. A specific molecular marker to diagnose existing high-grade dysplasia or impending malignant transformation is yet to be identified. Moving forward it is important to advance technology in isolating and identifying high-risk molecular markers from cyst fluid while considering their increased utilization in the evaluation of PCLs