Evidences have shown that dysbiosis could promote the progression of colorectal cancer (CRC). However, the association of dysbiosis and prognosis of CRC is barely investigated. Therefore, we used 16S rRNA gene sequencing approach to determine differences in microbiota among tumor tissues of different prognosis and found that Fusobacterium nucleatum and Bacteroides fragilis were more abundant in worse prognosis groups, while Faecalibacterium prausnitzii displayed higher abundance in survival group. To further explore the prognostic value of the found bacteria, Kaplan–Meier and Cox proportional regression analyses were used and the results exhibited that high abundance of F. nucleatum and B. fragilis were independent indicators of poor patient's survival. Besides, the expression of major inflammatory mediator were analyzed using PCR and western blot methods, and it turned out that high abundance of F. nucleatum was associated with increased expression of TNF-α, β-catenin and NF-κB, while COX-2, MMP-9 and NF-κB were positively related with high B. fragilis level, and high level of F. prausnitzii showed lower expression of β-catenin, MMP-9 and NF-κB. Moreover, immunohistochemical analysis indicated that KRAS and BRAF expression were prominent in F. nucleatum and B. fragilis high abundance group, while MLH1 showed lower expression. In conclusion, F. nucleatum, B. fragilis and F. prausnitzii can be identified as useful prognostic biomarkers for CRC, and dysbiosis might worsen the patients' prognosis by up-regulating gut inflammation level.

The molecular biological mechanisms underlying the evolutionary biologic changes leading to carcinogenesis remain unclear. The main objective of our study was to explore the evolution of the microbiota community and molecules related with CRC in the dynamic transition from normal colon epithelium to premalignant adenoma with the aid of an ‘adenoma–carcinoma sequence’ mouse CRC model induced by DMH. We generated a modified mouse CRC model induced by DMH for DNA sequences, and characterized the molecular networks. Data from 454 pyrosequencing of the V3- V5 region of the 16S rDNA gene and immunohistochemical detection of APC, P53, K-RAS and BRAF genes were assessed with Principal coordinates, UniFrac, and Kruskal-Wallis rank sum test. The inflammatory group showed enrichment of Bacteroidetes and Porphyromonadaceae (P < 0.01). OTUs affiliated with Firmicutes were enriched in the hyperproliferative group (P < 0.01). Rikenellaceae and Ruminococcaceae showed an increasing trend during the CRC process while the opposite pattern was observed for Prevotellaceaeand Enterobacteriaceae. OTUs related to Alistipes finegoldii were significantly increased during CRC development, P53, K-RAS and BRAF, were gradually increased (P < 0.05). Conversely, expression of APC was decreased during the course of development of CRC. Our results demonstrate that the biological evolutionary shift of gut microbiota, characterized by a gradual decrease in ‘driver’ bacteria and an increase in DNA damage-causing bacteria, is accompanied by tumor development in the CRC model. The synergistic actions of microbiota dysbiosis and effects of bacterial metabolites on related molecular events are proposed to contribute to the progression of CRC tumorigenesis.

ObjectiveTo compare the numbers of positive and total lymph nodes and prognosis in gastric cancer patients whose perigastric lymph node retrieval was performed by surgeons and pathologists.MethodsWe conducted a retrospective analysis of clinical and follow-up data from 1, 056 patients who underwent gastric cancer D2 radical lymph node resection between January 2008 and December 2010 in the Gastrointestinal Surgery Department of Yantai Yuhuangding Hospital. The follow-up ended in December 2015. Patients were divided into two groups according to the specialty of physicians who performed the postoperative perigastric lymph node retrieval: the surgeon group (475 cases) and the pathologist group (581 cases). The numbers of positive and total perigastric lymph nodes and the 3- and 5-year survival were compared between gastric cancer patients in the two groups overall and stratified by TNM stage (the 7th Edition of the American Joint Committee on Cancer).ResultsOverall, the numbers of positive and total lymph nodes were significantly higher in the surgeon group than in the pathologist group (6.53±4.07 vs. 4.09±3.70, P=0.021; 29.64±11.50 vs. 20.71±8.56, P<0.001). Further analysis showed that the total number of lymph nodes in stage I patients (19.40±9.62 vs. 15.45±8.59, P=0.011) and the numbers of positive and total lymph nodes in stage II (1.38±1.08 vs. 0.87±1.55, P=0.031; 25.35±10.80 vs. 16.75±8.56, P<0.001) and stage III patients (8.11±6.91 vs. 6.66±5.12, P=0.026; 32.34±12.55 vs. 25.45±8.31, P<0.001) were significantly higher in the surgeon group than in the pathologist group. The survival analysis showed that the 3- and 5-year survival of stage II and III patients was significantly higher in the surgeon group than in the pathologist group (82.0% vs. 73.1%, 69.5% vs. 61.2%, P=0.038; 49.2% vs. 38.9%, 36.3% vs. 28.0%; P=0.045).ConclusionsCompared with retrieval performed by pathologists, postoperative perigastric lymph node retrieval performed by surgeons was associated with significant increase in the total lymph node number of stage I patients, the numbers of positive and total lymph nodes of stage II and III patients, and the survival of stage II and stage III gastric cancer patients.

ObjectiveIn this research, we explored the effect of long non-coding RNA (lncRNA) AOC4P on gastrointestinal stromal tumor (GIST) cells.Materials and methodsThe expression of lncRNA AOC4P in tissues was detected by real-time PCR (RT-PCR). The epithelial–mesenchymal transition (EMT)-related proteins in tissues were analyzed by Western blot. The experiment included negative control group (CN), silence AOC4P group (si AOC4P), and silence negative control group (si CT). RT-PCR, MTT, Scratch, Transwell, and Annexin V-FITC methods were used to detect the expression of lncRNA AOC4P, cell proliferation, cell migration ability, cell invasion ability, and apoptosis, respectively. The EMT-related proteins including TGF-β, ZEB1, Vimentin, Snail, and E-cadherin were analyzed by Western blot.ResultsThe expression of lncRNA AOC4P and the expression of EMT-related proteins in high-risk GISTs were higher than that in low- and intermediate-risk GISTs (P<0.05). It was revealed that cell proliferative migration and invasive ability in si AOC4P group was decreased than that in CN and si CT groups (P<0.05), and cell apoptosis in si AOC4P group was higher than that in si CT group. The results of Western blot demonstrated that the expression of TGF-β1, ZEB1, Vimentin, and Snail in si AOC4P group were lower than that in si CT and CN group (P<0.05), and the expression of E-cadherin in si AOC4P group was higher than that in si CT and CN group (P<0.05).