Case report: a precancerous lesion associated with HPV in the anal canal diagnosed by magnifying endoscopy with narrow-band imaging and resected by endoscopic submucosal dissection.

Although anal cancer remains rarely diagnosed in the world, its frequency is rising, especially in high-risk groups. The prognosis of advanced anal cancer is poor. However, there are still few reports on the endoscopic diagnosis and treatment of early anal cancer and its precancerous lesions. A 60-year-old woman was referred to our hospital for endoscopic treatment of a flat precancerous lesion in the anal canal, which was identified by narrow-band imaging (NBI) and confirmed by pathological examination in another hospital. The pathological results showed a high-grade squamous intraepithelial lesion (HSIL) in the biopsy specimen, and immunochemistry staining showed P16 positive, suggesting HPV infection. We performed pre-resection endoscopic examination for the patient. A lesion with a clear margin and tortuous dilated vessels was revealed under magnifying endoscopy with NBI (ME-NBI), which stayed unstained after iodine spraying. The lesion was successfully removed en bloc using ESD without complications, and the resected specimen was a low-grade squamous intraepithelial lesion (LSIL) with positive immunochemistry staining of P16. The patient underwent follow-up coloscopy a year after ESD, and the anal canal healed well with no suspicious lesions found. From this case, we can learn that ESD is safe and effective for curative resection of precancerous lesions of the anal canal.

Asporin represses gastric cancer apoptosis via activating LEF1-mediated gene transcription independent of ß-catenin.

Asporin (ASPN) presents in the tumor microenvironment and exhibits a cancer-promoting effect as a stroma protein. Even though ASPN has already been observed inside cancer cells, the functions of intracellular ASPN and its underlying mechanisms remain unknown. Here we reported that ASPN was upregulated in different stages of gastric cancer (GC), and associated with a poor prognosis. Moreover, we found that ASPN markedly inhibited GC cell apoptosis and promoted cell growth in vitro and in vivo. Further mechanism investigations revealed that ASPN directly binding to lymphoid enhancer-binding factor 1 (LEF1) and promoted LEF1-mediated gene transcription independent of ß-catenin, the classic co-factor in the Wnt/LEF1 pathway. We also demonstrated that ASPN selectively facilitated LEF1 binding to and activating the promoters of PTGS2, IL6, and WISP1 to promote their transcription. The suppression of cell apoptosis by ASPN overexpression could be attenuated by LEF1 knockdown or 100 µM aspirin (PTGS2 inhibitor), and siASPN mediated apoptosis could be rescued by LEF1 ectopic expression or adding recombinant IL6. Therefore, we concluded that ASPN repressed GC cell apoptosis via activating LEF1-mediated gene transcription independent of ß-catenin, which could serve as a potential prognostic biomarker in GC patients.

Exosomal Sonic Hedgehog derived from cancer-associated fibroblasts promotes proliferation and migration of esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is one of the most common and aggressive malignancies in China. Cancer-associated fibroblasts (CAFs) can actively communicate with and stimulate tumor cells, thereby contributing to the development and progression of tumors. Yet, whether CAFs-derived exosomes have a role in the progression of ESCC is largely unknown. Here, we find that Sonic Hedgehog (SHH) is highly expressed in CAFs lysis solution, conditioned medium of cultured CAFs (CAF-CM) and CAFs-derived exosomes, and esophageal cancer cell lines educated by CAF-CM and CAFs-derived exosomes can improve their growth and migration abilities in vitro and in vivo. Besides, those effects can be partly neutralized by cyclopamine, inhibitor of the Hedgehog signaling pathway. Thus, our research elucidates the crucial role of CAFs-derived exosomes in the growth and progression of ESCC, and may open up new avenues in the treatment of ESCC.

RBBP8/CtIP suppresses P21 expression by interacting with CtBP and BRCA1 in gastric cancer.

RB Binding Protein 8 (RBBP8) was previously reported being involved in DNA double-strand break (DSB) repair in cancers. However, there is no systematic study about the specific functions and related mechanisms of RBBP8 in gastric carcinogenesis. Through immunohistochemistry staining of paired gastric cancer (GC) tissues, adjacent high-grade intraepithelial neoplasia (HGIEN) tissues, and non-cancerous tissues, we found RBBP8 expression was upregulated in both HGIEN and GC tissues. Functional experiments showed the knockdown of RBBP8 inhibited cell proliferation and colony formation ability. This is mainly achieved through the role of RBBP8 in facilitating G1/S transition and promoting Cyclin D1 and CDK4 level. Then the interaction between RBBP8, BRCA1, and CtBP was revealed by co-immunoprecipitation (co-IP) and immunofluorescence confocal imaging. Moreover, we found RBBP8 acted as an adapter in this complex and RBBP8 overexpression enhanced the nucleus location of BRCA1. RBBP8 overexpression could inhibit P21 expression and HDAC (histone deacetylase) inhibitor Trichostatin A (TSA) eliminated this effect. The HDAC activity of CtBP-RBBP8-BRCA1 complex was also further verified by HDAC activity assay. Through Chromatin immunoprecipitation (ChIP), we found RBBP8 could induce P21 promoter histone deacetylation and inhibit P21 transcription. In conclusion, we found RBBP8 could promote the G1/S transition of GC cells by inhibiting P21 level. Moreover, we revealed the chromatin modification role of RBBP8, which could suppress the histone acetylation level of P21 promoter by recruiting CtBP co-repressor complex to BRCA1 binding site.

Identification of Gut Microbiota and Metabolites Signature in Patients With Irritable Bowel Syndrome.

Background and Aims: Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder. However, the underlying mechanism of IBS is not fully understood. The aim of this study was to investigate potential mechanism and novel biomarkers of IBS through evaluation of the metabolomic and microbiologic profile. Methods: Fecal samples were collected from 15 irritable bowel syndrome patients and 15 healthy controls. By using gas chromatography coupled to time-of-flight mass spectrometry (GC-TOFMS) and 16S rDNA amplicon sequencing, fecal metabolites and microbiota of healthy controls and the IBS patients were measured. Results: IBS patients had a significantly differential metabolite profile as compared to healthy controls, and 4 clusters with 31 metabolites, including a group of amino acids and fatty acids, were significantly up-regulated as compared to the healthy controls. In addition, 19 microbes were significantly up-regulated, and 12 microbes were down-regulated in the IBS group, when compared with the healthy controls. Some clusters of fecal metabolites or microorganisms were significantly correlated with the severity of IBS symptoms, such as the frequency of abdominal pain/discomfort and the number of bowel movements. Correlation of the metabolite levels with abundances of microbial genera showed some statistically significant metabolite-microbe associations. Four differentially abundant amino acids clustered together were positively correlated with some microbes, including Lachnospira, Clostridium, and so on. Conclusion: The finding of this study puts a global perspective on metabolomics and microbiota profiling in IBS patients and provides a theoretical basis for future research on pathophysiology of IBS.

Cyclin-Dependent Kinase Inhibitor 3 Promoted Cell Proliferation by Driving Cell Cycle from G1 to S Phase in Esophageal Squamous Cell Carcinoma.

Background and aims. Cyclin-dependent kinase inhibitor 3 (CDKN3) has been found playing a varying role in carcinogenesis, but its biological function in esophageal squamous cell carcinoma (ESCC) is unclear. The aim of this study was to demonstrate the role of CDKN3 in ESCC. Materials and Methods: Real-time PCR and Western blot was performed in 15 pairs of ESCC tissues and adjacent normal esophageal tissues. Then cell proliferation ability, cloning ability, cell cycle status and migration and invasion ability were explored in CDKN3 overexpressed TE1 cell line and CDKN3 siRNA transfected TE1 and KYSE70 cell lines. Finally, cell cycle related proteins CyclinD1, CDK4, pAKT, P53, P21, and P27 were tested by Western blot. Results: mRNA level was higher in 11 ESCC tissues compared to adjacent normal tissues, and an increased protein expression was further detected in 8 of those 11 ESCC tissues. Functional assays showed that CDKN3 overexpression promoted ESCC cell proliferation, colony formation, migration and invasion, and facilitated G1/S transition. Opposite results were also got after transfected with CDKN3 siRNA. Cell cycle associated protein pAKT, CyclinD1, CDK4 and P27 were upregulated and P53, P21 and were downregulated under CDKN3 overexpression. All the protein levels were found changed in the opposite direction when CDKN3 expression was disturbed by siRNA. Conclusions: Our study suggested that CDKN3 acted as an oncogene in human ESCC and may accelerate the G1/S transition by affecting CyclinD-CDK4 complex via regulating pAKT-p53-p21 axis and p27 independent of AKT.

Multi-omics Analysis of Gut Microbiota and Metabolites in Rats With Irritable Bowel Syndrome.

Irritable bowel syndrome (IBS) is a common gastrointestinal dysfunctional disease. The pathophysiology of IBS is, however, largely unknown. This study aimed to determine whether evaluation of fecal metabolite and microbiota profiles may offer an opportunity to identify a novel pathophysiological target for IBS, and to reveal possible gut microbe-metabolite associations. By using gas chromatography coupled to time-of-flight mass spectrometry (GC-TOFMS) and 16S rRNA gene sequencing, we measured fecal metabolites and microbiota of the control and water avoidance stress (WAS)-induced IBS rats. We found a significantly differential metabolite profile between the IBS and control groups; a cluster of metabolites was also found to be significantly associated with the amount of defecations. Moreover, the WAS group exhibited a decreased alpha diversity of the microbial population as compared to the control group. However, the characteristics of gut microbiota could not differentiate the IBS group from the control group. Correlation of the metabolite level with the number of microbial genera showed no significant association between the control and IBS groups. This study provides a global perspective on metabolomics and microbiota profiling in WAS-induced IBS model and a theoretical basis for research on the pathophysiology of IBS.

Asporin promotes cell proliferation via interacting with PSMD2 in gastric cancer.

Asporin (ASPN), a member of small leucine-rich repeat proteoglycan (SLRP) family of proteins, serves important roles in diverse biological responses and disease conditions. We tested the hypothesis that ASPN regulated proliferation of gastric cancer (GC) cells and identified its down-stream regulators. ASPN promoted the proliferation of GC cells. We identified the effector of this effect as proteasome 26S subunit non-ATPase 2 (PSMD2) which is known to regulate proliferation through suppression of DUSP7, WIP1 and PTEN and then inducing the phosphorylation of ERK, P38 and AKT. PSMD2 co-immunoprecipitated with ASPN from GC cell lysates and co-localized with PSMD2 inside GC cells. Moreover, knockdown of ASPN significantly increased the expression of DUSP7, WIP1 and PTEN and led to a repression in the phosphorylation of ERK, P38 and AKT. These changes were counteracted by knockdown of PSMD2. In conclusion, ASPN promotes cell proliferation by interacting with PSMD2, and down-regulation of its effectors and serves as a potential therapeutic target in GC.

FAM175B promotes apoptosis by inhibiting ATF4 ubiquitination in esophageal squamous cell carcinoma.

FAM175B is a reported regulator of p53 and suppresses tumorigenesis in numerous types of cancer, but very little is known about its function in esophageal squamous cell carcinomas (ESCCs), almost 70% of which exhibit mutations in p53. Here, we report that FAM175B expression is downregulated in high-grade intraepithelial neoplasia (t = 2.44, P = 0.031) and ESCC (t = 5.664, P < 0.001) tissues relative to that in adjacent normal esophageal tissues. Exogenous expression of FAM175B in ESCC cells resulted in a decrease in proliferation rate, inhibition of colony formation, and an increase in apoptosis rate. Knockdown of FAM175B produced the opposite results. Furthermore, confocal microscopy and coimmunoprecipitation assay showed that Activating transcription factor 4 (ATF4) colocalized and interacted with FAM175B. Ubiquitination assays revealed that FAM175B inhibited ubiquitin-dependent ATF4 degradation and elevated ATF4 protein level. Finally, luciferase reporter experiments further clarified that FAM175B promoted CHOP expression in an ATF4-dependent manner. Accordingly, the proapoptotic activity of FAM175B was significantly rescued by treatment with si-ATF4 and the CHOP inhibitor 4-PBA. In summary, FAM175B inhibited ATF4 ubiquitination and promoted ESCC cell apoptosis in a p53-independent manner. FAM175B expression loss may be an early diagnostic biomarker in ESCC patients.

Cytoplasmic Asporin promotes cell migration by regulating TGF-ß/Smad2/3 pathway and indicates a poor prognosis in colorectal cancer.

Previous studies revealed that Asporin (ASPN) is a potential mediator in the development of various types of cancer as a secreted stroma protein, but the function of ASPN inside the cancer cells remains largely unknown. Here, we demonstrated a higher expression level of ASPN in colorectal cancer (CRC) than matched normal tissues, and 25% (2/8) CRC showed copy number variation (CNV) gain/amplification in ASPN gene. Both higher ASPN expression levels and ASPN CNV gain/amplification indicated a worse prognosis in CRC patients. ASPN can promote proliferation, migration, and invasion of CRC cells, and inhibit apoptosis by activating Akt/Erk and TGF-ß/Smad2/3 signalings. Further investigations revealed that ASPN interacts with Smad2/3, facilitates its translocation into nucleus, and up-regulates the expression of Epithelial-mesenchymal transition (EMT) related genes. Rescue assays confirmed that TGF-ß signaling is essential for the effects of ASPN on promoting CRC cell migration and invasion. In conclusion, ASPN promotes the migration and invasion of CRC cells via TGF-ß/Smad2/3 pathway and could serve as a potential prognostic biomarker in CRC patients.

A nomogram for endoscopic screening in a high esophageal squamous cell cancer risk area: results from a population-based study.

BACKGROUND: Endoscopy is the main approach used for esophageal squamous cell carcinoma (ESCC) screening, especially in high-risk areas. However, little consensus has been achieved in recent ESCC screening programs, and endoscopists have selected patients only by age and family history. PATIENTS AND METHODS: To generate a proper strategy for selecting an eligible population for endoscopic screening based on demographic factors, lifestyle, and eating habits, a total of 7,830 residents in an area with a high risk of ESCC were recruited for this study. All participants underwent endoscopic examinations that were conducted by experienced endoscopists. Risk factors for ESCC and other lesions were selected by univariate and multivariate logistic regressions. A nomogram for the prediction of ESCC and premalignant lesions was constructed, which included information on age, sex, occupation, labor intensity, income, and mining exposure. Receiver operating characteristic (ROC) curve analysis was performed to present the predictive accuracy of the nomograms. RESULTS: The area under the curve (95% CI) was 0.749 (0.711-0.788) for this nomogram. By applying this nomogram, we could exclude 60% (4704/7830) of patients before endoscopy screening and detect all ESCC cases as well as most esophageal lesions in the remaining population. CONCLUSION: In conclusion, we provided a ready-to-use preclinical tool with the potential to select eligible people with high risk of ESCC for endoscopy screening.

Transcriptome and methylome profiling in a rat model of irritable bowel syndrome induced by stress.

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder that is associated with psychological stress. However, the full landscape of IBS­related epigenetic factors remains unveiled and needs to be elucidated. The water­avoidance stress (WAS) method was used to induce a rat IBS model. Each rat was monitored, and its defecation and behavior were recorded. Total colon RNA was isolated and subjected to Affymetrix GeneChip analysis. Reduced Representation Bisulfate Sequencing (RRBS) was applied to determine the genome­wide methylation pattern in both IBS and control rats. Rats with IBS egested a significantly increased amount of dry and loose stools compared with the control animals, without significant changes in body weight. Compared with the control group, 309 genes were upregulated and 224 genes were downregulated in the colon of the IBS rats. Notch signaling and focal adhesion were increased in the differentially expressed genes (DEGs). A total of 541 genes had significant lower methylation level and 626 genes had significantly higher methylation level in their promoter regions. Adherens junction and leukocyte transendothelial migration were enriched in the differentially methylated genes (DMGs). Few genes were identified in common in both DEGs and DMGs, suggesting that gene expression was not altered by promoter methylation. Reverse transcription­quantitative polymerase chain reaction validation revealed that the mRNA levels of SSX2IP, PARD3 and VCL were significantly downregulated in the IBS group, in accordance with hypermethylation of their promoters. In summary, the present study used a WAS­induced IBS rat model to provide transcriptome and methylome profiling. Most DEGs were associated with Notch signaling and focal adhesion, and only a few were altered by promoter methylation. The present results demonstrated that psychological stress could influence the integrity of the intestinal mucosa barrier and regulate inflammatory response.

Gene regulatory network construction identified NFYA as a diffuse subtype-specific prognostic factor in gastric cancer.

Lauren classification is a pathology-based gastric cancer (GC) subtyping system, which is widely used in the clinical treatment of patients with GC. However, genome-scale molecular characteristics to distinguish between diffuse (DF) and intestinal (IT) GC remain incompletely characterized, particularly at the transcriptional regulatory level. In the present study, gene regulatory networks were constructed using the Passing Attributes between Networks for Data Assimilation (PANDA) algorithm for DF, IT and mixed GC. The results indicated that >85% of transcription factor (TF)-target edges were shared among all three GC subtypes. In TF enrichment analysis, 13 TFs, including nuclear transcription factor Y subunit α (NFYA) and forkhead box L1, were activated in DF GC, whereas 8 TFs, including RELA proto-oncogene and T-cell leukemia homeobox 1 (TLX1), were activated in IT GC. Out of these identified TFs, NFYA [Hazard ratio (HR) (95% confidence interval, CI)=0.560 (0.349, 0.900), P=0.017] and sex determining region Y [HR (95% CI)=0.603 (0.375, 0.969), P=0.037] were identified as independent prognostic factors in DF GC, but not in IT GC, whereas TLX1 [HR (95% CI)=0.547 (0.321, 0.9325), P=0.027] was identified as an independent prognostic factor in IT GC, but not in DF GC. Verification at the cellular level was also performed; interference of NFYA expression using small interfering RNA in MGC803 cells (DF GC-derived cells) markedly inhibited cell growth and colony formation. Similar effects were also detected in SGC-7901 cells (IT GC-derived cells), but to a lesser extent. In conclusion, identified gene regulatory networks differed between distinct GC subtypes, in which the same TFs had different biological effects. Specifically, NFYA was identified as a DF subtype-specific independent prognostic factor in GC.

Cadherin Expression Shift Could Well Distinguish Esophageal Squamous Cell Carcinoma from Non- Cancerous Esophageal Tissues.

BACKGROUND: Biomarkers for esophageal squamous cell carcinoma (ESCC) identification with high sensitivity are not well established. Since abnormal expression of cadherins has been widely reported in cancer, we explored its feasibility as an ESCC biomarker. METHODS: Expression of E-cadherin and N-cadherin were detected in 150 esophageal tissues by immunohistochemistry. Staining strength and percentage in different subcellular structures of each specimen were evaluated by 2 independent pathologists. A logistic regression-based classifier derived from E-cadherin and N-cadherin staining was generated. RESULTS: E-cadherin exhibited decreased membrane expression in ESCC, while N-cadherin exhibited decreased expression in the nucleus but elevated expression in the cytoplasm. Both E-cadherin and N-cadherin could distinguish ESCC tissues from non-cancerous tissues (area under the curve (AUC) = 0.748, 0.801, respectively). E-cadherin and N-cadherin staining scores could be merged into a cadherin (CDH) logistic index, which showed better discrimination (AUC = 0.909) than E-cadherin or N-cadherin alone. Further investigation indicated that the CDH logistic index was significantly correlated with tumor size and differentiation in ESCC. CONCLUSION: Both E-cadherin and N-cadherin had a strong expression shift in ESCC compared with non-cancerous tissues. The CDH logistic index, a parameter integrating the expression data of both cadherins, could be used as a marker with high sensitivity and specificity in the identification of ESCC.

Factors associated with gastric adenocarcinoma and dysplasia in patients with chronic gastritis: a population-based study.

OBJECTIVE: Gastric cancer (GC) is one of the leading causes of death in China and other Asian countries. Recently, gastric endoscopy has become the main approach for GC screening, but the identification of high-risk individuals remains a challenge in GC screening programs. METHODS: There were 7,302 patients with chronic gastritis involved in this study. Endoscopic examinations were performed, and their demographic characteristics and lifestyle data were collected. Each possible associated factor of GC/premalignant and precursor lesions was evaluated by univariate and multivariate logistic regressions. Nomograms were used for visualization of those models, and receiver operating characteristic (ROC) curve analysis was used to present the predictive accuracy. RESULTS: We detected 8 (0.11%) gastric adenocarcinomas, 17 (0.23%) dysplasia cases, 14 (0.19%) hyperplasia cases, 52 (0.71%) intestinal metaplasia cases, 217 (2.97%) inflammatory lesions, 141 (1.93%) gastric ulcers, 10 (0.14%) atrophic gastritis cases, 1,365 (18.69%) erosive gastritis cases, and 5,957 (81.58%) superficial gastritis cases in 7,302 patients. The age (P<0.001), gender (P=0.086), labor intensity (P=0.018) and leek food intake (P=0.143) were identified as independent predictive factors of GC/premalignant lesions possibility. The corresponding nomogram exhibited an area under the curve (AUC) [95% confidence interval (95% CI)] of 0.82 (0.74-0.89) for the modeling group and 0.80 (0.75-0.85) for the validation group. The age (P=0.002), gender (P=0.024), smoking (P=0.002) and leek food intake (P=0.039) were independent predictive factors of precursor lesions possibility. The corresponding nomogram exhibited an AUC (95% CI) of 0.62 (0.60-0.65) for the modeling group and 0.61 (0.59-0.63) for the validation group. CONCLUSIONS: We identified several potential associated factors and provided a preclinical nomogram with the potential to predict the possibility of GC/premalignant and precursor lesions.