SCF/c-KIT Signaling Increased Mucin2 Production by Maintaining Atoh1 Expression in Mucinous Colorectal Adenocarcinoma. Int J Mol Sci. 2018;19. [PMID: 29786668 PMCID: PMC5983812 DOI: 10.3390/ijms19051541]

Network pharmacology combined with experimental validation reveals the mechanism of action of erpixing granules on functional dyspepsia

ETHNOPHARMACOLOGICAL RELEVANCE

Functional dyspepsia (FD) is a prevalent gastrointestinal disorder characterised by high incidence and recurrence rates, posing significant health risks. Erpixing Granules (EPX), approved by the National Food and Drug Administration in 2002, are known for their spleen and stomach invigorating properties, effectively treating FD. However, its mechanism of action remains unclear.

AIM OF THE STUDY

This study aims to elucidate EPX's mechanism of treating FD through network pharmacology, and experimental validation using FD animal models.

METHODS

In this study, the chemical composition of EPX in positive and negative ion modes was analyzed by UHPLC-Q-TOF MS. The mass spectral data were processed and analyzed using MS-DIAL software to automatically match compound fragment information and identify the known components with the compound database to obtain the active components of EPX. SwissTargetPrediction was used to obtain EPX targets, while FD-related targets were sourced from GeneCards, OMIM and DisGeNET databases. A protein-protein interaction (PPI) network was constructed using the STRING platform, and potential signalling pathways of EPX were determined through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Finally, an FD model was established in rates by administering a 0.1% iodoacetamide sucrose solution, followed by tail clamp stimulation to experimentally validate the network pharmacology findings.

RESULTS

Our results revealed 139 effective ingredients in EPX, targeting 60 core FD-related genes. PPI network analysis identified EGFR, CTNNB1 and NFκB1 as core target genes. The KEGG pathway analysis indicated that EPX can modulate FD progression through the PI3K/AKT signalling pathway. Animal experiments demonstrated EPX's capacity to increase body mass, food intake and food utilisation efficiency in FD rats, alongside increased gastric juice secretion, pepsin activity, trypsin activity, cholesterol, bile acid and bilirubin activity. HE examination revealed that EPX improved the inflammatory infiltration of gastric mucosal cells in rats. Furthermore, EPX also promoted gastric emptying and intestinal propulsion in mice. These results suggest that EPX improves spleen and stomach function, enhances the protective effect on the spleen and stomach and promotes food digestion and absorption. Immunofluorescence studies revealed upregulated expression of PI3K, AKT and ANO1 proteins in gastric tissue following EPX administration, while Western blotting indicated increased expression of SCF and C-kit proteins.

CONCLUSION

Suggesting EPX's anti-FD effect may involve the regulation of the SCF/C-kit signalling pathway and activation of downstream PI3K/AKT signalling pathway, thereby promoting gastrointestinal motility and improving FD symptoms.

Integrating scRNA-seq and bulk RNA-seq to characterize infiltrating cells in the colorectal cancer tumor microenvironment and construct molecular risk models

Colorectal cancer (CRC) is a malignancy that is both highly lethal and heterogeneous. Although the correlation between intra-tumoral genetic and functional heterogeneity and cancer clinical prognosis is well-established, the underlying mechanism in CRC remains inadequately understood. Utilizing scRNA-seq data from GEO database, we re-isolated distinct subsets of cells, constructed a CRC tumor-related cell differentiation trajectory, and conducted cell-cell communication analysis to investigate potential interactions across cell clusters. A prognostic model was built by integrating scRNA-seq results with TCGA bulk RNA-seq data through univariate, LASSO, and multivariate Cox regression analyses. Eleven distinct cell types were identified, with Epithelial cells, Fibroblasts, and Mast cells exhibiting significant differences between CRC and healthy controls. T cells were observed to engage in extensive interactions with other cell types. Utilizing the 741 signature genes, prognostic risk score model was constructed. Patients with high-risk scores exhibited a significant correlation with unfavorable survival outcomes, high-stage tumors, metastasis, and low responsiveness to chemotherapy. The model demonstrated a strong predictive performance across five validation cohorts. Our investigation involved an analysis of the cellular composition and interactions of infiltrates within the microenvironment, and we developed a prognostic model. This model provides valuable insights into the prognosis and therapeutic evaluation of CRC.

Inhibition of Soluble Stem Cell Factor Promotes Intestinal Mucosal Repair

BACKGROUND

Incidences of inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, are escalating worldwide and can be considered a global public health problem. Given that the gold standard approach to IBD therapeutics focuses on reducing the severity of symptoms, there is an urgent unmet need to develop alternative therapies that halt not only inflammatory processes but also promote mucosal repair. Previous studies have identified increased stem cell factor (SCF) expression in inflamed intestinal mucosal tissues. However, the role that SCF plays in mediating intestinal inflammation and repair has not been explored.

METHODS

Changes in the expression of SCF were evaluated in the colonic tissue of healthy mice and during dextran sodium sulfate (DSS)-induced colitis. Furthermore, mucosal wound healing and colitis severity were analyzed in mice subjected to either mechanical biopsy or DSS treatment, respectively, following intestinal epithelial cell-specific deletion of SCF or anti-SCF antibody administration.

RESULTS

We report robust expression of SCF by intestinal epithelial cells during intestinal homeostasis with a switch to immune cell-produced SCF during colitis. Data from mice with intestinal epithelial cell-specific deletion of SCF highlight the importance of immune cell-produced SCF in driving the pathogenesis of colitis. Importantly, antibody-mediated neutralization of total SCF or the specific SCF248 isoform decreased immune cell infiltration and enhanced mucosal wound repair following biopsy-induced colonic injury or DSS-induced colitis.

CONCLUSIONS

These data demonstrate that SCF functions as a pro-inflammatory mediator in mucosal tissues and that specific neutralization of SCF248 could be a viable therapeutic option to reduce intestinal inflammation and promote mucosal wound repair in individuals with IBD.

Orchestration of MUC2 - The key regulatory target of gut barrier and homeostasis: A review

The gut mucosa of human is covered by mucus, functioning as a crucial defense line for the intestine against external stimuli and pathogens. Mucin2 (MUC2) is a subtype of secretory mucins generated by goblet cells and is the major macromolecular component of mucus. Currently, there is an increasing interest on the investigations of MUC2, noting that its function is far beyond a maintainer of the mucus barrier. Moreover, numerous gut diseases are associated with dysregulated MUC2 production. Appropriate production level of MUC2 and mucus contributes to gut barrier function and homeostasis. The production of MUC2 is regulated by a series of physiological processes, which are orchestrated by various bioactive molecules, signaling pathways and gut microbiota, etc., forming a complex regulatory network. Incorporating the latest findings, this review provided a comprehensive summary of MUC2, including its structure, significance and secretory process. Furthermore, we also summarized the molecular mechanisms of the regulation of MUC2 production aiming to provide developmental directions for future researches on MUC2, which can act as a potential prognostic indicator and targeted therapeutic manipulation for diseases. Collectively, we elucidated the micro-level mechanisms underlying MUC2-related phenotypes, hoping to offer some constructive guidance for intestinal and overall health of mankind.

Artesunate delays the dysfunction of age-related intestinal epithelial barrier by mitigating endoplasmic reticulum stress/unfolded protein response

The impairment of the intestinal epithelial barrier and subsequent bacterial translocation are common in aging individuals, contributory to several local and systematic disorders. However, the underlying mechanism of the age-related degeneration has not been fully understood. In this study, we demonstrated that the intestinal KIT signaling declined and de-activated with aging, parallel with epithelial barrier dysfunction. Endoplasmic reticulum stress (ERS)/unfolded protein response (UPR) was obviously increased during aging. The ERS and its downstream IRE1α were highly activated in the aging colonic epithelium. Furthermore, by the use of Tunicamycin (Tm)-induced ERS mouse and cell models, we uncovered that the activity of the ERS/IRE1α accelerated the protein degradation of KIT via ubiquitin-proteasome pathway. The deficiency of KIT signaling further reduced the transcription of the tight junction protein Claudin-3. Of significance, Artesunate (ART) could be capable of ameliorating the detrimental effect of ERS/IRE1α, indicated by the re-gained KIT and Claudin-3 expressions and the restoration of the intestinal epithelial barrier. In conclusion, our present study provided novel evidence elucidating the ERS/IRE1α-induced loss of KIT and Claudin-3 in the aging colonic epithelium and also shed light on the protective effect of Artesunate on the intestinal epithelial barrier by blocking ERS/IRE1α activity during aging.

Moxibustion improves experimental colitis in rats with Crohn's disease by regulating bile acid enterohepatic circulation and intestinal farnesoid X receptor

OBJECTIVE

This study was conducted to explore the mechanism of intestinal inflammation and barrier repair in Crohn's disease (CD) regulated by moxibustion through bile acid (BA) enterohepatic circulation and intestinal farnesoid X receptor (FXR).

METHODS

Sprague-Dawley rats were randomly divided into control group, CD model group, mild moxibustion group and herb-partitioned moxibustion group. CD model rats induced by 2,4,6-trinitrobenzene sulfonic acid were treated with mild moxibustion or herb-partitioned moxibustion at Tianshu (ST25) and Qihai (CV6). The changes in CD symptoms were rated according to the disease activity index score, the serum and colon tissues of rats were collected, and the pathological changes in colon tissues were observed via histopathology. Western blot, immunohistochemistry (IHC) and immunofluorescence were used to evaluate the improvement of moxibustion on intestinal inflammation and mucosal barrier in CD by the BA-FXR pathway.

RESULTS

Mild moxibustion and herb-partitioned moxibustion improved the symptoms of CD, inhibited inflammation and repaired mucosal damage to the colon in CD rats. Meanwhile, moxibustion could improve the abnormal expression of BA in the colon, liver and serum, downregulate the expression of interferon-γ and upregulate the expression of FXR mRNA, and inhibit Toll-like receptor 4 (TLR4) and myeloid differentiation factor 88 (MyD88) mRNA. The IHC results showed that moxibustion could upregulate the expression of FXR and mucin2 and inhibit TLR4 expression. Western blot showed that moxibustion inhibited the protein expression of TLR4 and MyD88 and upregulated the expression of FXR. Immunofluorescence image analysis showed that moxibustion increased the colocalization sites and intensity of FXR with TLR4 or nuclear factor-κB p65. In particular, herb-partitioned moxibustion has more advantages in improving BA and upregulating FXR and TLR4 in the colon.

CONCLUSION

Mild moxibustion and herb-partitioned moxibustion can improve CD by regulating the enterohepatic circulation stability of BA, activating colonic FXR, regulating the TLR4/MyD88 pathway, inhibiting intestinal inflammation and repairing the intestinal mucosal barrier. Herb-partitioned moxibustion seems to have more advantages in regulating BA enterohepatic circulation and FXR activation. Please cite this article as: Shen JC, Qi Q, Han D, Lu Y, Huang R, Zhu Y, Zhang LS, Qin XD, Zhang F, Wu HG, Liu HR. Moxibustion improves experimental colitis in rats with Crohn's disease by regulating bile acid enterohepatic circulation and intestinal farnesoid X receptor. J Integr Med. 2023.

Gene Expression Profile Reveals a Prognostic Signature of Non–MSI-H/pMMR Colorectal Cancer

Studies have demonstrated that non–MSI-H/pMMR colorectal cancer (CRC) has a worse prognosis and relapse rate than microsatellite instability-high (MSI-H)/mismatch repair deficient (dMMR) CRC. Hence, searching for a novel tool to advance the prognostic management of non–MSI-H/pMMR CRC is vital. In this study, using three independent public cohorts and a clinical in-house cohort, we developed and validated a microsatellite stable–associated signature (MSSAS). The initial signature establishment was performed in GSE39582 (n = 454). This was followed by independent validation of this signature in The Cancer Genome Atlas–CRC (n = 312), GSE39084 (n = 54), and in-house cohort (n = 146). As a result, MSSAS was proven to be an independent risk factor for overall survival and relapse-free survival in non–MSI-H/pMMR CRC. Receiver operating characteristic analysis showed that MSSAS had a stable and accurate performance in all cohorts for 1, 3, and 5 years, respectively. Further analysis suggested that MSSAS performed better than age, gender, and the T, N, M, and AJCC stages, adjuvant chemotherapy, tumor mutation burden, neoantigen, and TP53, KRAS, BRAF, and PIK3CA mutations. The clinical validation was executed to further ensure the robustness and clinical feasibility of this signature. In conclusion, MSSAS might be a robust and promising biomarker for advancing clinical management of non–MSI-H/pMMR CRC.

Diverse expression patterns of mucin 2 in colorectal cancer indicates its mechanism related to the intestinal mucosal barrier

BACKGROUND

Abnormal expression patterns of mucin 2 (MUC2) have been reported in a variety of malignant tumors and precancerous lesions. Reduced MUC2 expression in the intestinal mucosa, caused by various pathogenic factors, is related to mechanical dysfunction of the intestinal mucosa barrier and increased intestinal mucosal permeability. However, the relationship between MUC2 and the intestinal mucosal barrier in patients with colorectal cancer (CRC) is not clear.

AIM

To explore the relationship between MUC2 and intestinal mucosal barrier by characterizing the multiple expression patterns of MUC2 in CRC.

METHODS

Immunohistochemical staining was performed on intestinal tissue specimens from 100 CRC patients, including both cancer tissues and adjacent normal tissues. Enzyme-linked immunosorbent assays were performed on preoperative sera from 66 CRC patients and 20 normal sera to detect the serum levels of MUC2, diamine oxide (DAO), and D-lactate (D-LAC). The relationship between MUC2 expression and clinical parameters was calculated by the χ² test or Fisher’s exact test. Prognostic value of MUC2 was evaluated by Kaplan-Meier curve and log-rank tests.

RESULTS

Immunohistochemical staining of 100 CRC tissues showed that the expression of MUC2 in cancer tissues was lower than that in normal tissues (54% vs 79%, P < 0.05), and it was correlated with tumor-node-metastasis (TNM) stage and lymph node metastasis in CRC patients (P < 0.05). However, the serum level of MUC2 in CRC patients was higher than that in normal controls, and was positively associated with serum levels of human DAO (χ² = 3.957, P < 0.05) and D-LAC (χ² = 7.236, P < 0.05), which are the biomarkers of the functional status of the intestinal mucosal barrier. And the serum level of MUC2 was correlated with TNM stage, tumor type, and distant metastasis in CRC patients (P < 0.05). Kaplan-Meier curves showed that decreased MUC2 expression in CRC tissues predicted a poor survival.

CONCLUSION

MUC2 in tissues may play a protective role by participating in the intestinal mucosal barrier and can be used as an indicator to evaluate the prognosis of CRC patients.

Consequence of distinctive expression of MUC2 in colorectal cancers: How much is actually bad?

Colorectal cancer (CRC) exhibits complex pathogenesis via compromised intestinal mucosal barrier. It is accepted that goblet cells secrete mucin which line the intestinal mucosal barrier and offer wide range protection and maintain the gut integrity. The principal mucin in the small and large intestine which is Mucin2 (MUC2) is predominantly expressed in the goblet cells which play a pivotal role in intestinal homeostasis. Its disruption is associated with diverse diseases and carcinomas. MUC2 has lately been identified as a principal marker in various mechanisms and secretory cell lineage. While MUC2 expression is regulated by various modulators, alterations in its expression are associated with immunomodulation, differences in tumor immunity and also regulation of microbiota. In the light of current literature, the present review explicates the regulation, functional mechanisms and essential role of MUC2 in colorectal cancer and aids in providing deep understanding of pathogenesis of the disease and also specifies the importance of the MUC2 in gaining more insights about the subtypes of colorectal cancer and how it can succour in approximating the prognosis and survival of the patients.

The Diverse Roles of the Mucin Gene Cluster Located on Chromosome 11p15.5 in Colorectal Cancer

Colorectal cancer (CRC), the third most common malignant tumor in the world, shows multiple complex and pathologies based on the impaired structure and function of the intestinal mucosal barrier. Goblet cells secrete mucins, which are involved in the formation of the intestinal mucosal barrier and not only lubricate and protect the intestinal mucosa but also participate in the processes of cell adhesion, intercellular signal transduction, and immune regulation. It is accepted that the disordered expression and dysfunction of mucins are associated with the occurrence and development of CRC. This article focuses on the secretory mucins encoded by a gene cluster located on chromosome 11p15.5 and systematically reviews their composition, regulation, function, and role in CRC, to deepen the understanding of the pathogeneses of CRC and to provide a new basis and ideas for the treatment of CRC.