Objective To investigate the expressions of long non-coding RNA antisense non-cod-ing RNA in the INK4 locus(lncRNA ANRIL)and microRNA-181b-5p(miR-181b-5p)in the serum of patients with colon cancer complicated with type 2 diabetes mellitus(T2DM)and their correlations with lymph node metastasis.Methods A total of 117 patients with colon cancer complicated with T2DM in the hospital from May 2019 to August 2022 were selected as colon cancer with T2DM group and divided into lymph node metastasis group(n=56)and no lymph node metastasis group(n=61)according to the lymph node metastasis status.Additionally,117 healthy volunteers with physical ex-aminations in the same period were selected as control group.Reverse transcription real-time quantita-tive PCR was used to detect the relative expression levels of serum lncRNA ANRIL and miR-181b-5p.Logistic regression analysis was conducted to explore the factors influencing lymph node metastasis in patients with colon cancer complicated with T2DM.Receiver operating characteristic(ROC)curve was plotted to analyze the diagnostic values of serum lncRNA ANRIL and miR-181b-5p levels for lymph node metastasis in patients with colon cancer complicated with T2DM.Pearson correlation a-nalysis was used to investigate the correlation between serum lncRNA ANRIL and miR-181b-5p ex-pression in patients with colon cancer complicated with T2DM.Results Compared with the control group,patients in the colon cancer with T2DM group had significant increased serum lncRNA ANRIL level and decreased miR-181b-5p level(P＜0.01).Compared with the no lymph node metastasis group,patients in the lymph node metastasis group had significant increased serum lncRNA ANRIL level and decreased miR-181b-5p level(P＜0.01).There were significant differences in TNM stage,degree of differentiation,and glycated hemoglobin(HbA1C)between the lymph node metas-tasis group and the no lymph node metastasis group(P＜0.05).History of diabetes,TNM stage,degree of differentiation,HbA1 C,and lncRNA ANRIL were influencing factors for lymph node me-tastasis(P＜0.05),while miR-181b-5p was a protective factor against lymph node metastasis(P＜0.05).There was a negative correlation between serum lncRNA ANRIL and miR-181b-5p levels(r=-0.440,P＜0.001).The ROC curve result showed that the areas under the curve(AUCs)for the diagnosis of lymph node metastasis by serum lncRNA ANRIL,miR-181b-5p,and their com-bination were 0.800,0.837 and 0.930 respectively.The combined diagnostic value was significant-ly higher than that of lncRNA ANRIL(Z=2.956,P=0.003)and miR-181b-5p(Z=2.117,P=0.034)alone.Conclusion Patients with colon cancer complicated with T2DM have increased ser-um lncRNA ANRIL level and decreased miR-181b-5p level,and both two indexes are correlated with lymph node metastasis.

OBJECTIVE To investigate the improvement effects of limonin on intestinal injury and intestinal flora disturbance in rats with ulcerative colitis （UC） and its mechanism. METHODS UC rat models were established， and 70 rats with successful modeling were randomly divided into model group， limonin low-， medium-， and high-dose groups （12.5， 25， 50 mg/kg）， and sulfasalazine group （positive control group，500 mg/kg）， with 14 rats in each group. Another 14 rats were selected as the control group. After modeling， each group was given the corresponding drug or equal amount of normal saline， once a day， for 2 weeks. Twenty-four hours after the last administration， the general condition of rats was observed and the body weight was measured， and colon tissue was collected for colonic mucosal damage index （CMDI） scoring； the levels of interleukin-1β （IL-1β）， IL-6 and tumor necrosis factor-α （TNF-α） in colon tissue were detected； the pathological changes of colon tissue were observed； the protein expressions of Claudin-1， Occludin， ZO-1， high mobility group protein B1 （HMGB1） and receptor for advanced glycation end products （RAGE） in colon tissue were detected； fecal 16S rRNA sequencing was used to detect the relative abundance of zhangxiaxia5287@163.com intestinal microbiota in rats. RESULTS Compared with the control group， the rats in the model group were in poor mental state， with darker fur， irritable mood， disordered arrangement of colon glands， inflammatory cell infiltration， cell necrosis and edema； CMDI score， the levels of IL-1β， IL-6 and TNF-α， protein expressions of HMGB1 and RAGE in colon tissue， the relative abundance of Proteobacteria and Bacteroidetes were significantly increased （P＜0.05）； body weight， the protein expressions of Claudin-1， Occludin and ZO-1 in colon tissue， the relative abundance of Firmicutes in the intestine were significantly decreased （P＜0.05）. Compared with the model group， general situation and pathological damage of colonic tissue in limonin groups were improved， the levels of the above indicators were significantly reversed （P＜0.05）， and in a dose-dependent manner （P＜0.05）； there was no significant difference in various indexes between sulfasalazine group and limonin high-dose group （P＞0.05）. CONCLUSIONS Limonin can improve intestinal injury and intestinal flora disturbance in UC model rats， the mechanism of which may be associated with the down-regulation of HMGB1/RAGE signaling pathway.