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Extracell Vesicles Circ Nucleic Acids 2020;1:20-56 I http://dx.doi.org/10.20517/evcna.2020.10 Page 37

a longitudinal cohort of euglycemic and diabetic individuals. We report many significant associations
between EV inflammatory protein levels and diabetes status. Most importantly, we found that vascular
endothelial growth factor A (VEGF-A) was significantly associated with diabetes status in our longitudinal
cohort. The plasma levels of this angiogenic factor were higher in EVs from individuals with diabetes
compared to euglycemic individuals. Furthermore, EV levels of VEGF-A were significantly associated
with homeostatic model assessments of insulin resistance (HOMA-IR) and b-cell function (HOMA-B),
which are mathematical models that measure diabetes severity. To examine whether EVs with different
inflammatory cargo can affect target cell behavior, we performed in vitro cell biological assays to assess the
functional effects of these EVs on endothelial cells. We found that EVs from diabetic individuals induced
actin cytoskeletal rearrangements including cell lamellipodia formation and increased cellular migration
when compared to EVs from euglycemic individuals. Here we demonstrate that EV inflammatory protein
profiles differ by diabetes status. Hence, our data suggest that EVs may play important roles in the end
organ complications of diabetes mellitus, such as peripheral vascular disease.

22. IMP1 modulates extracellular vesicle production in the GI tract through regulation of

endosome and autophagy pathways

Authors: Sarah F. Andres, Madeline Kuhn, Ranjan Preet, Aurora Blucher, John Favate, Sukanya Das,
Shun Liang, Louis Parham, Priya Chatterji, Wei Zhang, Jiegang Yang, Kathryn E. Hamilton, Premal Shah,
Gordon Mills, Dan A. Dixon, Wei Guo, Anil K. Rustgi
E-mail: andress@ohsu.edu
Affiliations:
School of Medicine, Oregon Health and Science University, Portland, OR, USA.
Department of Molecular Biosciences, University of Kansas, Lawrence, KS, USA.
Department of Genetics, Rutgers University, Newark, NJ, USA.
Divisions of Gastroenterology, Children's Hospital of Philadelphia and University of Pennsylvania, Philadelphia,
PA, USA.
Columbia University Irving Medical Center New York, NY, USA.
Abstracts:
Background: RNA binding proteins regulate protein expression through coordinated binding to a series of
related transcripts referred to as an RNA operon. Previous work demonstrates context and tissue specific
roles for the RNA binding protein insulin-like growth factor 2 mRNA binding protein 1 (IMP1) in the
context of cancer, especially colorectal cancer (CRC). Recent studies have linked IMP1 to extracellular
vesicles and demonstrated that Imp1 is a potential regulator of autophagy during intestinal repair in
response to damage. The endosomal, extracellular vesicle, and autophagy pathways are interrelated;
however, a direct role for IMP1 in coordinating these pathways in the GI tract has not been explored.
Hypothesis: IMP1 alters vesicle production and secretion by altering expression of vesicle pathway proteins
in colon cancer and the non-transformed intestinal epithelium.
Methods: Ribosomal profiling and RNA sequencing were used to compare transcript and translational
efficiency profiles between IMP1 null and IMP1- overexpressing CRC cell lines. Extracellular vesicles were
assessed by nanoparticle tracking analysis, western blot, and electron microscopy in CRC cells and non-
transformed, mouse intestinal enteroids. Effects of IMP1 on endosome, vesicle, and autophagy pathways
were assessed by electron microscopy, immunofluorescence, and western blot in cell lines and enteroids.
Results: A number of extracellular vesicle and exosome-related pathways were the most significant
differentially regulated pathways by gene ontogeny analysis of RNA sequencing data in IMP1 null vs. IMP1-
-10
-10
overpressing CRC cells (P = 1.78×10 , 2.43×10 ). Over 42% of the changed transcripts are associated with a