Kim TH, et al. J Gastric Cancer. 2023 Jan;23:e11. https://doi.org/10.5230/jgc.2023.23.e11

Hye-Kyung Jung, Seung Joo Kang, Yong Chan Lee, Hyo-Joon Yang, Seon-Young Park, Cheol Min Shin, Sung Eun Kim, Hyun Chul Lim, Jie-Hyun Kim, Su Youn Nam, Woon Geon Shin, Jae Myung Park, Il Ju Choi, Jae Gyu Kim, and Miyoung Choi, Korean College of Helicobacter and Upper Gastrointesinal Research. Gut and Liver -0001;0:. https://doi.org/10.5009/gnl20288

Early gastric cancer (EGC) can be treated by minimally invasive endoscopic resection and has an excellent prognosis. The aim of this study was to investigate whether repeated esophagogastroduodenoscopy (EGD) screening is an effective method for detecting EGC that can be treated by endoscopic resection. For patients diagnosed with gastric cancer in the Korean National Cancer Center screening program, we analyzed the incidence of gastric cancer, clinicopathological characteristics, and treatment modality according to whether they had (repeated screening group) or not (infrequent screening group) undergone EGD screening within 2 years before diagnosis. Of the 18,414 patients who underwent EGD, 81 (0.44%) were found to have gastric cancer. Incidence of gastric cancer in repeated screening group was lower than that of infrequent screening group (multiple adjusted odds ratio=0.45, 95% confidence interval: 0.26-0.77, P=0.004). The proportion of EGCs was 96% (25 of 26) n the repeated screening group and 71% (34 of 48) in the infrequent screening group (P=0.01). Mean (SD) tumor size was smaller [1.9 (1.2) vs. 3.0 (1.6) cm, P=0.01] and the proportion of intramucosal cancer was higher [81% (21 of 26) vs. 50% (24 of 48), P=0.02] in the former than in the latter. Endoscopic resection was performed more frequently in the repeated screening group [54% (14 of 26) vs. 23% (11 of 48), P=0.007]. Repeated endoscopic screening within 2 years decreased the incidence of gastric cancer and endoscopic resection could be applied to more patients who underwent EGD screening within 2 years.

Non-coding RNAs have been drawing increasing attention in recent years as functional data suggest that they play important roles in key cellular processes. N-BLR is a primate-specific long non-coding RNA that modulates the epithelial-to-mesenchymal transition, facilitates cell migration, and increases colorectal cancer invasion. We performed multivariate analyses of data from two independent cohorts of colorectal cancer patients and show that the abundance of N-BLR is associated with tumor stage, invasion potential, and overall patient survival. Through in vitro and in vivo experiments we found that N-BLR facilitates migration primarily via crosstalk with E-cadherin and ZEB1. We showed that this crosstalk is mediated by a pyknon, a short ~20 nucleotide-long DNA motif contained in the N-BLR transcript and is targeted by members of the miR-200 family. In light of these findings, we used a microarray to investigate the expression patterns of other pyknon-containing genomic loci. We found multiple such loci that are differentially transcribed between healthy and diseased tissues in colorectal cancer and chronic lymphocytic leukemia. Moreover, we identified several new loci whose expression correlates with the colorectal cancer patients’ overall survival. The primate-specific N-BLR is a novel molecular contributor to the complex mechanisms that underlie metastasis in colorectal cancer and a potential novel biomarker for this disease. The presence of a functional pyknon within N-BLR and the related finding that many more pyknon-containing genomic loci in the human genome exhibit tissue-specific and disease-specific expression suggests the possibility of an alternative class of biomarkers and therapeutic targets that are primate-specific.

Su Youn Nam. Gut and Liver 2017;11:323-34. https://doi.org/10.5009/gnl15557