Ubiquitin-like 3 as a new protein-sorting factor for small extracellular vesicles.

Ubiquitin-like 3 (UBL3) is a well-conserved ubiquitin-like protein (UBL) in eukaryotes and regulates the ubiquitin cascade, but the significant roles of UBL3 in cellular processes remained unknown. Recently, UBL3 was elucidated to be a post-translational modification factor that promotes protein sorting to small extracellular vesicles (sEVs). Proteins sorted into sEVs have been studied as etiologies of sEV-related diseases. Also, there have been attempts to construct drug delivery systems (DDSs) by loading proteins into sEVs. In this review, we introduce the new concept that UBL3 has a critical role in the protein-sorting system and compare structure conservation between UBL3 and other UBLs from an evolutionary perspective. We conclude with future perspectives for the utility of UBL3 in sEV-related diseases and DDS.Key words: UBL3, small extracellular vesicles, protein sorting, ubiquitin-like protein, post-translational modification.

[Evaluation of Intra-abdominal fat distribution using X-ray CT data for detection of rectal cancer].

To develop a novel method of detecting rectal cancer, we assessed relationships between intra-abdominal fat distribution and rectal cancer in Japanese patients. Subjects comprised 38 patients with rectal cancer apparent on CT-colonography and 110 other cases. The intra-abdominal fat area was determined by calculating pixel distribution with attenuation values from -140 HU to -40 HU. The area of intra-abdominal fat was measured on axial images using an interslice gap of 10 mm. Profile curves of intra-abdominal fat were in the plane direction from diaphragm to anus. Of note is the fact that Ogura's peak, a secondary small peak around the rectal cancer, was apparent on the profile of intra-abdominal fat, with 73.7% of rectal cancers displaying Ogura's peak. In comparison, only 19.1% of other cases displayed Ogura's peak on this profile. The relationship between fat and rectal cancer is difficult to explain. However, making good use of these results showing intra-abdominal fat distribution, a computer-aided diagnosis (CAD) system for detecting rectal cancer according to the presence of Ogura's peak has potential as a method of mass screening. As only 148 cases were investigated in the present study, the accumulation of additional data is needed. More detailed studies with larger patient populations are warranted.