CXCL8 expression is associated with advanced stage, right sidedness, and distinct histological features of colorectal cancer

From Ulcerative Colitis to Metastatic Colorectal Cancer: The Neutrophil Contribution

Ulcerative colitis (UC) is an inflammatory colon and rectum disease affecting approximately 5 million people worldwide. There is no cure for UC, and approximately 8% of patients with UC develop colorectal cancer (CRC) by gradual acquisition of mutations driving the formation of adenomas and their progression to adenocarcinomas and metastatic disease. CRC constitutes 10% of total cancer cases worldwide and 9% of cancer deaths. Both UC and CRC have an increasing incidence worldwide. Although the epithelium has been well studied in UC and CRC, the contribution of neutrophils is less clear. Neutrophils are rapidly recruited in excessive amounts from peripheral blood to the colon during UC, and their overactivation in the proinflammatory UC tissue environment contributes to tissue damage. In CRC, the role of neutrophils is controversial, but emerging evidence suggests that their role depends on the evolution and context of the disease. The role of neutrophils in the transition from UC to CRC is even less clear. However, recent studies propose neutrophils as therapeutic targets for better clinical management of both diseases. This review summarizes the current knowledge on the roles of neutrophils in UC and CRC.

CMTM4 promotes the motility of colon cancer cells under radiation and is associated with an unfavorable neoadjuvant chemoradiotherapy response and patient survival in rectal cancer

Neoadjuvant chemoradiotherapy (nCRT) is the standard treatment for locally advanced rectal cancer (LARC). Pathological complete regression is closely linked to disease outcomes. However, biomarkers predicting nCRT response and patient survival are lacking for LARC. In the present study, the clinical characteristics and follow-up information of 228 patients with LARC were retrospectively collected. Immunohistochemistry (IHC), reverse transcription-quantitative PCR (RT-qPCR), Kaplan-Meier and multivariate analyses were used to evaluate the expression and predict the role of CKLF-like MARVEL transmembrane domain member 4 (CMTM4) in LARC. Additionally, lentiviral short hairpin (sh)RNA was used to interfere with CMTM4 expression. The phenotype of CMTM4-knockdown LoVo cells was determined by colony formation, migration and invasion assays under irradiation (IR) treatment. RNA-sequencing (RNA-seq) analysis was also used to explore the CMTM4-regulated genes in LoVo-shCMTM4 cells compared with control cells. RT-qPCR was then used to confirm the expression of these CMTM4-regulated genes. CMTM4 expression in pre-nCRT tissues indicated an unfavorable response and a short disease-free survival (DFS) with LARC. The expression of CMTM4 significantly increased following nCRT treatment. Additionally, CMTM4 knockdown increased the proliferation, migration and invasion of colon cancer cells; however, IR disrupted the cell migration and invasion induced by CMTM4 knockdown. RNA-seq analysis, the Tumor Immune Estimation Resource database and RT-qPCR indicated that CMTM4 was involved in different signaling pathways and regulated immune-related genes such as cluster of differentiation 66b, chemokine (CXC motif) ligand 8 (CXCL8) and programmed cell death 1. Furthermore, CXCL8 expression was found to be negatively associated with CMTM4 expression in patients with LARC by IHC and RT-qPCR. CXCL8 expression on invasion margin regions in post-operative tissues was also an inferior predictor of DFS in patients with LARC. In conclusion, CMTM4 may predict the nCRT response and outcomes in patients with LARC.

Single-Cell Transcriptomics Reveals Cellular Heterogeneity and Drivers in Serrated Pathway-Driven Colorectal Cancer Progression

Serrated lesions are common precancerous pathways in colorectal cancer (CRC), but the process by which they progress to malignancy remains unclear. We aimed to elucidate this progression through a single-cell RNA landscape. We conducted single-cell RNA sequencing on three normal colonic tissues and fifteen SLs (including HPs, SSLs, SSLD, and TSAs) and integrated these data with datasets containing tumor samples. We identified three invasive malignant epithelial cell subtypes related to CRC progression: SLC1, SLC2, and tumor cell. SLC1, specific to SSLs, is involved in cell proliferation and shows a continuum of malignancy in gene expression. TSA-specific SLC2 exhibited FOXQ1 upregulation and active EMT, indicating invasiveness. The trajectory analysis showed that HPs do not progress to cancer, and different SL types are linked to the MSI status of advanced CRCs. We validated molecular drivers in premalignant lesions and later carcinogenesis. In the tumor microenvironment, CAF and pre-CAF fibroblast subtypes associated with progression were identified. During the premalignant stage, SLC1 triggered CD8+ T cell responses, while at the advanced stage, CAFs promoted tumor invasion and metastasis via FN1-CD44, influencing tumor progression and the treatment response. Our findings highlight transcriptional changes across serrated pathway stages, aiding in early CRC diagnosis and treatment.

Establishing Criteria for Tumor Necrosis as Prognostic Indicator in Colorectal Cancer

Tumor necrosis has been reported to represent an independent prognostic factor in colorectal cancer, but its evaluation methods have not been described in sufficient detail to introduce tumor necrosis evaluation into clinical use. To study the potential of tumor necrosis as a prognostic indicator in colorectal cancer, criteria for 3 methods for its evaluation were defined: the average percentage method (tumor necrosis percentage of the whole tumor), the hotspot method (tumor necrosis percentage in a single hotspot), and the linear method (the diameter of the single largest necrotic focus). Cox regression models were used to calculate cancer-specific mortality hazard ratios (HRs) for tumor necrosis categories in 2 colorectal cancer cohorts with more than 1800 cases. For reproducibility assessment, 30 cases were evaluated by 9 investigators, and Spearman's rank correlation coefficients and Cohen's kappa coefficients were calculated. We found that all 3 methods predicted colorectal cancer-specific survival independent of other prognostic parameters, including disease stage, lymphovascular invasion, and tumor budding. The greatest multivariable HRs were observed for the average percentage method (cohort 1: HR for ≥ 40% vs. <3% 3.03, 95% CI, 1.93-4.78; cohort 2: HR for ≥ 40% vs. < 3% 2.97; 95% CI, 1.63-5.40). All 3 methods had high reproducibility, with the linear method showing the highest mean Spearman's correlation coefficient (0.91) and Cohen's kappa (0.70). In conclusion, detailed criteria for tumor necrosis evaluation were established. All 3 methods showed good reproducibility and predictive ability. The findings pave the way for the use of tumor necrosis as a prognostic factor in colorectal cancer.

Network pharmacology and bioinformatics to identify the molecular mechanisms of Gleditsiae Spina against colorectal cancer

Objective

In this study, network pharmacology, bioinformatics and molecular docking were used to explore the active phytochemicals, hub genes, and potential molecular mechanisms of Gleditsiae Spina in treating of colorectal cancer..

Methods

The targets of Gleditsiae Spina, and targets related to CRC were derived from databases. We identified the hub genes for Gleditsiae Spina anti-colorectal cancer following the protein-protein-interaction (PPI) network. Furthermore, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment were used to analyze the hub genes from a macro perspective. Finally, we verified the hub genes by molecular docking, GEPIA, HPA, and starBase database.

Results

We identified nine active phytochemicals and 36 intersection targets. The GO enrichment analysis results showed that Gleditsiae Spina may be involved in gene targets affecting multiple biological processes, including response to radiation, response to ionizing radiation, cyclin-dependent protein kinase holoenzyme complex, serine/threonine protein kinase complex, cyclin-dependent protein serine/threonine kinase regulator activity and protein kinase regulator activity. KEGG enrichment analysis results indicated that the P53 signaling pathway, IL-17 signaling pathway, Toll-like receptor signaling pathway, PI3K-Akt signaling pathway, and JAK-STAT signaling pathway were mainly related to the effect of Gleditsiae Spina on colorectal cancer. Molecular docking analysis suggested that the active phytochemicals of Gleditsiae Spina could combine well with hub genes (PTGS1, PIK3CG, CCND1, CXCL8 and ADRB2).

Conclusion

This study provides clues for further study of anti-CRC phytochemicals as well as their mechanisms of provides a basis for their development model.

The Cytokine Network in Colorectal Cancer: Implications for New Treatment Strategies

Colorectal cancer (CRC) is one of the most frequent tumor entities worldwide with only limited therapeutic options. CRC is not only a genetic disease with several mutations in specific oncogenes and/or tumor suppressor genes such as APC, KRAS, PIC3CA, BRAF, SMAD4 or TP53 but also a multifactorial disease including environmental factors. Cancer cells communicate with their environment mostly via soluble factors such as cytokines, chemokines or growth factors to generate a favorable tumor microenvironment (TME). The TME, a heterogeneous population of differentiated and progenitor cells, plays a critical role in regulating tumor development, growth, invasion, metastasis and therapy resistance. In this context, cytokines from cancer cells and cells of the TME influence each other, eliciting an inflammatory milieu that can either enhance or suppress tumor growth and metastasis. Additionally, several lines of evidence exist that the composition of the microbiota regulates inflammatory processes, controlled by cytokine secretion, that play a role in carcinogenesis and tumor progression. In this review, we discuss the cytokine networks between cancer cells and the TME and microbiome in colorectal cancer and the related treatment strategies, with the goal to discuss cytokine-mediated strategies that could overcome the common therapeutic resistance of CRC tumors.