Drug repurposing screening and mechanism analysis based on human colorectal cancer organoids.

Colorectal cancer (CRC) is a highly heterogeneous cancer and exploring novel therapeutic options is a pressing issue that needs to be addressed. Here, we established human CRC tumor-derived organoids that well represent both morphological and molecular heterogeneities of original tumors. To efficiently identify repurposed drugs for CRC, we developed a robust organoid-based drug screening system. By combining the repurposed drug library and computation-based drug prediction, 335 drugs were tested and 34 drugs with anti-CRC effects were identified. More importantly, we conducted a detailed transcriptome analysis of drug responses and divided the drug response signatures into five representative patterns: differentiation induction, growth inhibition, metabolism inhibition, immune response promotion, and cell cycle inhibition. The anticancer activities of drug candidates were further validated in the established patient-derived organoids-based xenograft (PDOX) system in vivo. We found that fedratinib, trametinib, and bortezomib exhibited effective anticancer effects. Furthermore, the concordance and discordance of drug response signatures between organoids in vitro and pairwise PDOX in vivo were evaluated. Our study offers an innovative approach for drug discovery, and the representative transcriptome features of drug responses provide valuable resources for developing novel clinical treatments for CRC.

Network pharmacology-based strategy to investigate the bioactive ingredients and molecular mechanism of Evodia rutaecarpa in colorectal cancer.

BACKGROUND: Evodia rutaecarpa, a traditional herbal drug, is widely used as an analgesic and antiemetic. Many studies have confirmed that Evodia rutaecarpa has an anticancer effect. Here, our study explored the bioactive ingredients in Evodia rutaecarpa acting on colorectal cancer (CRC) by utilizing network pharmacology. METHODS: We clarified the effective ingredients and corresponding targets of Evodia rutaecarpa. CRC-related genes were obtained from several public databases to extract candidate targets. Candidate targets were used to construct a protein-protein interaction (PPI) network for screening out core targets with topological analysis, and then we selected the core targets and corresponding ingredients for molecular docking. Cell proliferation experiments and enzyme-linked immunosorbent assays (ELISAs) verified the anticancer effect of the bioactive ingredients and the results of molecular docking. RESULTS: Our study obtained a total of 24 bioactive ingredients and 100 candidate targets after intersecting ingredient-related targets and CRC-related genes, and finally, 10 genes-TNF, MAPK1, TP53, AKT1, RELA, RB1, ESR1, JUN, CCND1 and MYC-were screened out as core targets. In vitro experiments suggested that rutaecarpine excelled isorhamnetin, evodiamine and quercetin in the inhibition of CRC cells and the release of TNF-α was altered with the concentrations of rutaecarpine. Molecular docking showed that rutaecarpine could effectively bind with TNF-α. CONCLUSION: The pairs of ingredients-targets in Evodia rutaecarpa acted on CRC were excavated. Rutaecarpine as a bioactive ingredient of Evodia rutaecarpamight effectively inhibit the proliferation of CRC cells by suppressing TNF-α.

Spatially resolved expression landscape and gene-regulatory network of human gastric corpus epithelium.

Molecular knowledge of human gastric corpus epithelium remains incomplete. Here, by integrated analyses using single-cell RNA sequencing (scRNA-seq), spatial transcriptomics, and single-cell assay for transposase accessible chromatin sequencing (scATAC-seq) techniques, we uncovered the spatially resolved expression landscape and gene-regulatory network of human gastric corpus epithelium. Specifically, we identified a stem/progenitor cell population in the isthmus of human gastric corpus, where EGF and WNT signaling pathways were activated. Meanwhile, LGR4, but not LGR5, was responsible for the activation of WNT signaling pathway. Importantly, FABP5 and NME1 were identified and validated as crucial for both normal gastric stem/progenitor cells and gastric cancer cells. Finally, we explored the epigenetic regulation of critical genes for gastric corpus epithelium at chromatin state level, and identified several important cell-type-specific transcription factors. In summary, our work provides novel insights to systematically understand the cellular diversity and homeostasis of human gastric corpus epithelium in vivo.

Relationships of tumor differentiation and immune infiltration in gastric cancers revealed by single-cell RNA-seq analyses.

Gastric cancers are highly heterogeneous malignant tumors. To reveal the relationship between differentiation status of cancer cells and tumor immune microenvironments in gastric cancer, single-cell RNA-sequencing was performed on normal mucosa tissue, differentiated gastric cancer (DGC) tissue, poorly differentiated gastric cancer (PDGC) tissue and neuroendocrine carcinoma (NEC) tissue sampled from surgically resected gastric cancer specimens. We identified the signature genes for both DGC and PDGC, and found that signature genes of PDGC strongly enriched in the epithelial-mesenchymal transition (EMT) program. Furthermore, we found that DGC tends to be immune-rich type whereas PDGC tends to be immune-poor type defined according to the density of tumor-infiltrating CD8+ T cells. Additionally, interferon alpha and gamma responding genes were specifically expressed in the immune-rich malignant cells compared with immune-poor malignant cells. Through analyzing the mixed adenoneuroendocrine carcinoma, we identified intermediate state malignant cells during the trans-differentiation process from DGC to NEC, which showed double-negative expressions of both DGC marker genes and NEC marker genes. Interferon-related pathways were gradually downregulated along the DGC to NEC trans-differentiation path, which was accompanied by reduced CD8+ cytotoxic T-cell infiltration. In summary, molecular features of both malignant cells and immune microenvironment cells of DGC, PDGC and NEC were systematically revealed, which may partially explain the strong tumor heterogeneities of gastric cancer. Especially along the DGC to NEC trans-differentiation path, immune-evasion was gradually enhanced with the decreasing activities of interferon pathway responses in malignant cells.

Single-cell profiling reveals molecular basis of malignant phenotypes and tumor microenvironments in small bowel adenocarcinomas.

Small bowel adenocarcinomas (SBAs) are rare malignant tumors with a high mortality rate, and their molecular characteristics are still largely unexplored. Here we performed single-cell RNA sequencing for tumor samples from 12 SBA patients and predicted drug candidates for SBA. We identified four prevalent subtypes of malignant cells with distinct signatures including cell cycle program, mitochondria program, metabolism program and epithelial-mesenchymal transition (EMT) program. The progression relationships of these four subtypes of malignant cells were also revealed, which started from the cell cycle program, through the mitochondria program and then progressing into either the metabolism program or the EMT program. Importantly, ligand-receptor interaction pairs were found to be specifically enriched in pairs of EMT-program malignant cells and highly exhausted CD8+ T cells, suggesting that cancer cell subpopulations with EMT features may contribute most to the exhaustion of T cells. We also showed that the duodenal subtype of SBA exhibited molecular features more similar to gastric cancer whereas jejunal subtype of SBA more similar to colorectal cancer. Especially, we predicted specific drugs for SBA based on differential gene expression signatures between malignant cells and normal epithelial cells of SBA, and verified more potent inhibitory effects of volasertib and tozasertib for SBA cancer cells than conventional drugs of SBA at the same concentration, which provides new clues for treatments of SBA. In summary, our study provides a blueprint of the molecular signatures of both tumor cells and tumor microenvironment cells in SBA and reveals potential targets and drug candidates for its clinical treatments.

A glycolysis-related two-gene risk model that can effectively predict the prognosis of patients with rectal cancer.

BACKGROUND: Aerobic glycolysis is an emerging hallmark of cancer. Although some studies have constructed glycolysis-related prognostic models of colon adenocarcinoma (COAD) based on The Cancer Genome Atlas (TCGA) database, whether the COAD glycolysis-related prognostic model is appropriate for distinguishing the prognosis of rectal adenocarcinoma (READ) patients remains unknown. Exploring critical and specific glycolytic genes related to READ prognosis may help us discover new potential therapeutic targets for READ patients. RESULTS: Three gene sets, HALLMARK_GLYCOLYSIS, REACTOME_GLYCOLYSIS and REACTOME_REGULATION_OF_GLYCOLYSIS_BY_FRUCTOSE_2_6_BISPHOSPHATE_METABOLISM, were both significantly enriched in both COAD and READ through glycolysis-related gene set enrichment analysis (GSEA). We found that six genes (ANKZF1, STC2, SUCLG2P2, P4HA1, GPC1 and PCK1) were independent prognostic genes in COAD, while TSTA3 and PKP2 were independent prognostic genes in READ. Glycolysis-related prognostic model of COAD and READ was, respectively, constructed and assessed in COAD and READ. We found that the glycolysis-related prognostic model of COAD was not appropriate for READ, while glycolysis-related prognostic model of READ was more appropriate for READ than for COAD. PCA and t-SNE analysis confirmed that READ patients in two groups (high and low risk score groups) were distributed in discrete directions based on the glycolysis-related prognostic model of READ. We found that this model was an independent prognostic indicator through multivariate Cox analysis, and it still showed robust effectiveness in different age, gender, M stage, and TNM stage. A nomogram combining the risk model of READ with clinicopathological characteristics was established to provide oncologists with a practical tool to evaluate the rectal cancer outcomes. GO enrichment and KEGG analyses confirmed that differentially expressed genes (DEGs) were enriched in several glycolysis-related molecular functions or pathways based on glycolysis-related prognostic model of READ. CONCLUSIONS: We found that a glycolysis-related prognostic model of COAD was not appropriate for READ, and we established a novel glycolysis-related two-gene risk model to effectively predict the prognosis of rectal cancer patients.

Long non-coding RNA profile study identifies a metabolism-related signature for colorectal cancer.

BACKGROUND: Heterogeneity in colorectal cancer (CRC) patients provides novel strategies in clinical decision-making. Identifying distinctive subgroups in patients can improve the screening of CRC and reduce the cost of tests. Metabolism-related long non-coding RNA (lncRNA) can help detection of tumorigenesis and development for CRC patients. METHODS: RNA sequencing and clinical data of CRC patients which extracted and integrated from public databases including The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) were set as training cohort and validation cohort. Metabolism-related genes were acquired from Kyoto Encyclopedia of Genes and Genomes (KEGG) and the metabolism-related lncRNAs were filtered using correlation analysis. The risk score was calculated based on lncRNAs with prognostic value and verified through survival curve, receiver operating characteristic (ROC) curve and risk curve. Prognostic factors of CRC patients were also analyzed. Nomogram was constructed based on the results of cox regression analyses. The different immune status was observed in the single sample Gene Set Enrichment Analysis (ssGSEA). RESULTS: The training cohort and the validation cohort enrolled 432 and 547 CRC patients respectively. A total of 23 metabolism-related lncRNAs with prognostic value were screened out and 10 of which were significantly differentially expressed between tumour and normal tissues. Finally, 8 lncRNAs were used to establish a risk score (DICER1-AS1, PCAT6, GAS5, PRR7-AS1, MCM3AP-AS1, GAS6-AS1, LINC01082 and ADIRF-AS1). Patients were divided into high-risk and low-risk groups according to the median of risk scores in training cohort and the survival curves indicated that the survival prognosis was significantly different. The area under curve (AUC) of the ROC curve in two cohorts were both greater than 0.6. The age, tumour stage and risk score were selected as independent factors and used to construct a nomogram to predict CRC patients' survival rate with the c-index of 0.806. The ssGSEA indicated that the risk score was associated with immune cells and functions. CONCLUSIONS: Our systematic study established a metabolism-related lncRNA signature to predict outcomes of CRC patients which may contribute to individual prevention and treatment.

Downregulation of FABP5 Suppresses the Proliferation and Induces the Apoptosis of Gastric Cancer Cells Through the Hippo Signaling Pathway.

Fatty acid binding protein 5 (FABP5) has been reported to play an important role in various cancers. We found that high FABP5 expression was associated with poor histological differentiation and vascular invasion. High FABP5 expression indicated a poor prognosis. Downregulation of FABP5 suppressed cell proliferation, cell migration and invasion, and induced cell apoptosis. Bioinformatic analysis revealed that the Hippo signaling pathway was related to FABP5. We found that overexpression of yes-associated protein 1 (YAP1) could partially reverse the effect of FABP5 knockdown on growth and apoptosis. The FABP5 inhibitor SBFI-26 suppressed the proliferation and promoted the apoptosis of gastric cancer (GC) cells and interfered with the Hippo signaling pathway by inhibiting YAP1. Our data suggested that FABP5 might act as a potential target associated with the Hippo signaling pathway for GC treatment.

Prognosis Prediction for Colorectal Cancer Patients: A Risk Score Based on The Metabolic-Related Genes.

Risk assessment has high prognostic value in patients with colorectal cancer (CRC), and the use of proper models is an effective approach frequently used to evaluate cancer progression for further treatment plans. Alterations in metabolism are confirmed to be a significant feature of tumor cells and have been an intense focus in disease research. Here, we mined the genes that were differentially expressed in CRC tissues compared to paired normal samples from a public database and then constructed a novel assessment system for the prognosis of patients based on the value of a risk score considering the expression status of metabolism-related genes after screening. The score successfully stratified patients by risk and was externally verified in our study. Moreover, we built a nomogram combining the score and clinical parameters to predict patient survival using a visual method. The results suggested that the risk score was well fit and could provide assistance for the individual treatment of CRC patients in the clinic.

Expression Signature of the AT-Rich Interactive Domain Gene Family Identified in Digestive Cancer.

BACKGROUND: The AT-rich interactive domain (ARID) gene family of 15 proteins has an important role in development and proliferation. Gene expression alterations of the ARID family are correlated with the pathogenesis of digestive cancer, but systematic research has not been conducted. METHODS: We obtained transcriptome sequencing data, clinical characteristics and stemness indices of the seven main types of digestive cancer (cholangiocarcinoma, colon adenocarcinoma, oesophageal carcinoma, liver hepatocellular carcinoma, pancreatic adenocarcinoma, rectum adenocarcinoma and stomach adenocarcinoma) from public pan-cancer data to combine the analysis of the expression and prognostic signature of the ARID gene family. The stromal and immune scores for each sample were calculated to explore the correlations between the ARID gene family members and the tumour microenvironment. RESULTS: After screening, 1,920 digestive cancer samples were included in our study. ARID3C was expressed at low levels throughout the digestive cancer samples. The expression levels of ARID1A and JARID1C were relatively high, but there was striking heterogeneity across the different cancer types for specific family members. The survival analysis indicated that many genes were significantly related to the prognosis of patients with liver hepatocellular carcinoma. The stemness indices, stromal score, and immune score analysis showed that the expression of a single ARID gene had characteristic consistency in each tumour, but the levels among the different genes still varied. CONCLUSION: Our systematic study of the ARID gene family and its association with the immune infiltrate, tumour microenvironment and outcomes of digestive cancer patients focus on the complex relations and indicate the need to study each ARID member as an individual in a specific cancer type.

Characteristic Analysis of Featured Genes Associated With Stemness Indices in Colorectal Cancer.

Cancer stem cells (CSCs) with self-renewal play an important role in tumor initiation and progression and are associated with drug resistance in cancer therapy. Here, we investigated the characteristics of stem cell-related genes in colorectal cancer (CRC) based on datasets from The Cancer Genome Atlas (TCGA) and Oncomine. We found that the stemness indices were significantly overexpressed in CRC tissues and were associated with patient survival. Weighted gene co-expression network analysis (WGCNA) was performed to determine the modules of stemness and featured genes. Significant modules and 8 genes (BUB1, BUB1B, CHEK1, DNA2, KIF23, MCM10, PLK4, and TTK) were selected according to the inclusion criteria. Expression analyses of transcription and protein levels confirmed internal correlation and their relevance with the tumor. Functional analysis of these genes demonstrated their enrichment in pathways, including checkpoint, chromosomal region and protein serine/threonine kinase activity. These results suggested that the characteristics of the featured genes fit well with CRC pathology and could provide new strategies for individual prevention and treatment.

Assessment for Risk Status of Colorectal Cancer Patients: A Novel Prediction Model Based on Immune-Related Genes.

Heterogeneity in patients with colorectal cancer (CRC) leads to different strategies in clinical decision making. Identifying distinctive subgroups in patients contributes to develop more individualized treatments. This study constructed a novel prediction model for the prognosis of CRC patients based on the value of risk score combining the expression status of immune-related genes and coefficients. In this study, we built an interactive network of prognosis-related immune genes and transcription factors and adopted several methods to verify the accuracy of model. Moreover, we assessed the correlation between risk score and immune infiltration. The results suggested that the model was well fit and the risk score could be an independent predictive factor for CRC patients. This model has high application value in the clinic.

Comparison Between Laparoscopic and Open Resection Following Neoadjuvant Chemoradiotherapy for Mid-Low Rectal Cancer Patients: A Meta-Analysis.

INTRODUCTION: The optimal approach of resection for mid-low rectal cancer after neoadjuvant chemoradiotherapy (nCRT) is still controversial. The aim of this meta-analysis was to clarify the safety and feasibility of laparoscopic surgery compared with open resection. MATERIALS AND METHODS: We performed a literature search for studies on PubMed, Embase and Cochrane Library up to March 1, 2018. Review Manager software was applied for data analysis. We used weighted mean difference (WMD) for continuous parameters and odds ratio (OR) for dichotomous variables. Confidence interval (CI) was set at 95% and a P value <.05 was considered statistically significant. RESULTS: A total of seven studies met the inclusion criteria for the meta-analysis: 466 patients in laparoscopic group and 491 in open group. The pooled result revealed that laparoscopic resection had a favorable blood loss (WMD = -116.88 mL; 95% CI: -189.78 to -43.99; P = .002), analogous lymph nodes harvest (WMD = -0.30; 95% CI: -1.29 to 0.70; P = .56), less postoperative complications (OR = 0.63; 95% CI: 0.46-0.88; P = .006), shorter time to pass first flatus (WMD = -0.76 day; 95% CI: -1.00 to -0.51; P < .00001), and stay in hospital (WMD = -2.71 days; 95% CI: -4.54 to -0.88; P = .004), despite similar operating time (WMD = 11.17 minutes; 95% CI: -14.37 to 36.70; P = .39). CONCLUSIONS: Laparoscopic resection might be a technically safe and feasible approach for mid-low rectal cancer patients after nCRT compared with open resection.

MMP9 is involved in HO-1-mediated upregulation of apical junctional complex in Caco-2 cells under oxygen-glucose deprivation.

Ischemia reperfusion injury is a critical factor in the recovery process after intestine trauma and the functional restoration of intestinal reconstruction. This study was the first to explore the expression of apical junctional complex (AJC) induced by heme oxygenase-1 (HO-1) in Caco-2 cells in oxygen-glucose deprivation (OGD) models. Here we showed that HO-1 was upregulated after OGD. Notably, activation of HO-1 largely enhanced the expression of AJC proteins including Claudin-4, E-cadherin and ß-catenin in Caco-2 cells, but decreased the expression of matrix metalloproteinase 9 (MMP9). Knockdown of HO-1 attenuated the OGD-induced overexpression of AJC proteins but promoted the expression of MMP9. Interestingly, inhibition of MMP9 further enhanced AJC expression. These results suggest that HO-1 is involved in OGD-evoked upregulation of AJC proteins, which is partly mediated by MMP9 pathway. High expression of HO-1 may play an important role in the pathophysiological process of ischemia reperfusion injury and has potential clinical value for the treatment of intestine related diseases.