Circular RNAs (circRNAs) are regarded as a novel class of widespread endogenous non-coding RNAs, which may play important roles in tumorigenesis by regulating gene expression. Nevertheless, the characterization of circRNAs in epithelial ovarian cancer (EOC) remains largely unknown. This study aimed to investigate circRNA expression profiles in EOC. A total of 54 EOC specimens and 54 normal ovarian tissues (controls) were collected. circRNA-sequencing based circRNA expression profiles were identified in 4 EOC specimens and compared with 4 normal ovarian tissues. circRNA-sequencing data were validated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) in the 54 EOC specimens and 54 normal ovarian tissues. The association between differentially expressed circRNAs and various clinicopathological features of EOC was determined using a non-parametric test. Univariate analysis was performed using the log-rank test. A total of 4,388 circRNAs (2,556 up- and 1,832 downregulated; fold change of >= 2 and P<0.05) were identified to be differentially expressed in the EOC specimens compared with the normal ovarian tissues. Of these, the levels of 6 circRNAs (circBNC2, circEXOC6B, circFAM13B, circ-N4BP2L2, circRHOBTB3 and circCELSR1) were confirmed by RT-qPCR. Our data further indicated that these 6 circRNAs were associated with various clinicopathological features of EOC. More importantly, we found that circEXOC6B and circ-N4BP2L2 may act as novel prognostic biomarkers in patients with EOC. On the whole, the results of this study indicate that differentially expressed circRNAs may participate in the pathogenesis of EOC and may thus have potential for use as novel diagnostic and prognostic biomarkers for EOC. Future experiments with larger sample sizes are required to verify the current findings and illuminate the regulatory mechanisms of action of circRNAs in the tumorigenesis of EOC.

Objective: We investigated the clinical significance of preoperative pan-immune-inflammation value (PIV) in patients with colorectal cancer (CRC).Methods: In this retrospective study, 366 cases who underwent surgery for CRC were enrolled. Their clinical data were collected. PIV was calculated with the formula PIV = [neutrophil count (10⁹/L)× platelet count (10⁹/L) × monocyte count (10⁹/L) /lymphocyte count (10⁹/L). Patients were divided into high PIV (> median PIV) and low PIV (< median PIV) groups. The relationship between PIV and clinicopathological features of CRC was investigated. Receiver operating characteristic (ROC) curve was plotted to indicate the value of immune-inflammatory biomarkers (IIBs) in predicting the TNM stage of CRC, and the area under the curve (AUC) was calculated to evaluate the actual clinical value of IIBs. AUC > 0.5 and closer to 1 indicated the better predictive efficacy. The influencing factors of PIV in CRC were analyzed.Results: We found that PIV was positively correlated with tumor size (r = 0.300, p < 0.05), carcinoembryonic antigen (CEA) (r = 0.214, p < 0.05) and carbohydrate antigen 125 (CA-125) (r = 0.249, p < 0.05), but negatively correlated with albumin (Alb) (r = −0.242, p < 0.05). PIV was significantly different in patients with different tumor locations (left or right), surgical methods (laparotomy versus laparoscopic surgery) (p < 0.05), and patients with different pathological T stages, N-stage and TNM stages (p < 0.05). ROC curve analysis of IIBs showed the AUC of PIV was greater than other markers when combined with CEA or carbohydrate antigen 19–9 (CA19–9). Multivariate regression analysis identified T stage, CEA, Alb, and tumor size as the independent influential factors of PIV in CRC.Conclusion: PIV is associated with the tumor stage in patients with CRC, which may be useful in preoperative assessment of CRC.

Smoking and risk of cholangiocarcinoma: a systematic review and meta-analysis Smoking and risk of cholangiocarcinoma: a systematic review and meta-analysis

Inflammatory bowel disease (IBD) is a chronic non-specific inflammatory disease that occurs in the intestinal tract. It is mainly divided into two subtypes, i.e., the Crohn’s disease (CD) and ulcerative colitis (UC). At present, its pathogenesis has not been fully elucidated, but it has been generally believed that the environment, immune disorders, genetic susceptibility, and intestinal microbes are the main factors for the disease pathogenesis. With the development of the sequencing technology, microbial factors have received more and more attention. The gut microbiota is in a state of precise balance with the host, in which the host immune system is tolerant to immunogenic antigens produced by gut commensal microbes. In IBD patients, changes in the balance between pathogenic microorganisms and commensal microbes lead to changes in the composition and diversity of gut microbes, and the balance between microorganisms and the host would be disrupted. This new state is defined as dysbiosis. It has been confirmed, in both clinical and experimental settings, that dysbiosis plays an important role in the occurrence and development of IBD, but the causal relationship between dysbiosis and inflammation has not been elucidated. On the other hand, as a classic research method for pathogen identification, the Koch’s postulates sets the standard for verifying the role of pathogens in disease. With the further acknowledgment of the disease pathogenesis, it is realized that the traditional Koch’s postulates is not applicable to the etiology research (determination) of infectious diseases. Thus, many researchers have carried out more comprehensive and complex elaboration of Koch’s postulates to help people better understand and explain disease pathogenesis through the improved Koch’s postulates. Therefore, focusing on the new perspective of the improved Koch’s postulates is of great significance for deeply understanding the relationship between dysbiosis and IBD. This article has reviewed the studies on dysbiosis in IBD, the use of microbial agents in the treatment of IBD, and their relationship to the modified Koch’s postulates.