Prognostic and Predictive Value of BGN in Colon Cancer Outcomes and Response to Immunotherapy.

BACKGROUND: Colon cancer is one of the most frequent malignancies and causes high mortality worldwide. Exploring the tumor-immune interactions in the tumor microenvironment and identifying new prognostic and therapeutic biomarkers will assist in decoding the novel mechanism of tumor immunotherapy. BGN is a typical extracellular matrix protein that was previously validated as a signaling molecule regulating multiple processes of tumorigenesis. However, its role in tumor immunity requires further investigation. METHODS: The differentially expressed genes in three GEO datasets were analyzed, and BGN was identified as the target gene by intersection analysis of PPIs. The relevance between clinical outcomes and BGN expression levels was evaluated using data from the GEO database, TCGA and tissue microarray of colon cancer samples. Univariable and multivariable Cox regression models were conducted for identifying the risk factors correlated with clinical prognosis of colon cancer patients. Next, the association between BGN expression levels and the infiltration of immune cells as well as the process of the immune response was analyzed. Finally, we predicted the immunotherapeutic response rates in the subgroups of low and high BGN expression by TIS score, ImmuCellAI and TIDE algorithms. RESULTS: BGN expression demonstrated a statistically significant upregulation in colon cancer tissues than in normal tissues. Elevated BGN was associated with shorter overall survival as well as unfavorable clinicopathological features, including tumor size, serosa invasion and length of hospitalization. Mechanistically, pathway enrichment and functional analysis demonstrated that BGN was positively correlated with immune and stromal scores in the TME and primarily involved in the regulation of immune response. Further investigation revealed that BGN was strongly expressed in the immunosuppressive phenotype and tightly associated with the infiltration of multiple immune cells in colon cancer, especially M2 macrophages and induced Tregs. Finally, we demonstrated that high BGN expression presented a better immunotherapeutic response in colon cancer patients. CONCLUSION: BGN is an encouraging predictor of diagnosis, prognosis and immunotherapeutic response in patients with colon cancer. Assessment of BGN expression represents a novel approach with great promise for identifying patients who may potentially benefit from immunotherapy.

MicroRNA-95-3p inhibits cell proliferation and metastasis in colorectal carcinoma by HDGF.

BACKGROUND: MicroRNAs (miRNAs) play an important regulatory role in carcinogenesis and cancer progression. MiR-95-3p has been reported to be an oncogene in hepatocellular carcinoma. However, the role of miR-95-3p in colorectal carcinoma (CRC) remains unclear. METHODS: miR-95-3p was validated in an independent validation sample cohort of 215 CRC tissues. Functional assays, Cell proliferation (MTT) assay colony formation, wound healing, transwell and animal xenograft assays were used to determine the oppressor role of miR-95-3p in human CRC progression. Furthermore, Bioinformatics analysis, western blotting and dual-luciferase reporter assay were used to determine the mechanism by which miR-95-3p suppresses progression of CRC cells. RESULTS: In this study, we found that miR-95-3p was downregulated in CRC tissues. The low level of miR-95-3p in CRC tumors was correlated with aggressive clinicopathological characteristics, and it predicted poor prognosis in CRC patients. The overexpression of miR-95-3p significantly inhibited CRC cell proliferation, colony formation and metastasis in vitro and in vivo. Bioinformatic analysis further identified hepatoma-derived growth factor (HDGF) as a novel target of miR-95-3p in CRC cells. These findings suggest that miR-95-3p regulates CRC cell survival, partially through the downregulation of HDGF. CONCLUSIONS: Therefore, the miR-95-3p/HDGF axis might serve as a novel therapeutic target in patients with CRC.

Toll-like receptor 4 regulates spontaneous intestinal tumorigenesis by up-regulating IL-6 and GM-CSF.

Inflammation is as an important component of intestinal tumorigenesis. The activation of Toll-like receptor 4 (TLR4) signalling promotes inflammation in colitis of mice, but the role of TLR4 in intestinal tumorigenesis is not yet clear. About 80%-90% of colorectal tumours contain inactivating mutations in the adenomatous polyposis coli (Apc) tumour suppressor, and intestinal adenoma carcinogenesis in familial adenomatous polyposis (FAP) is also closely related to the germline mutations in Apc. The ApcMin/+ (multiple intestinal neoplasia) model mouse is a well-utilized model of FAP, an inherited form of intestinal cancer. In this study, ApcMin/+ intestinal adenoma mice were generated on TLR4-sufficient and TLR4-deficient backgrounds to investigate the carcinogenic effect of TLR4 in mouse gut by comparing mice survival, peripheral blood cells, bone marrow haematopoietic precursor cells and numbers of polyps in the guts of ApcMin/+ WT and ApcMin/+ TLR4-/- mice. The results revealed that TLR4 had a critical role in promoting spontaneous intestinal tumorigenesis. Significant differential genes were screened out by the high-throughput RNA-Seq method. After combining these results with KEGG enrichment data, it was determined that TLR4 might promote intestinal tumorigenesis by activating cytokine-cytokine receptor interaction and pathways in cancer signalling pathways. After a series of validation experiments for the concerned genes, it was found that IL6, GM-CSF (CSF2), IL11, CCL3, S100A8 and S100A9 were significantly decreased in gut tumours of ApcMin/+ TLR4-/- mice compared with ApcMin/+ WT mice. In the functional study of core down-regulation factors, it was found that IL6, GM-CSF, IL11, CCL3 and S100A8/9 increased the viability of colon cancer cell lines and decreased the apoptosis rate of colon cancer cells with irradiation and chemical treatment.

[Analysis on misdiagnosis of 271 patients with rectal cancer].

OBJECTIVE: To investigate the common reasons for the misdiagnosis of rectal cancer. METHODS: A retrospective study was performed in 568 cases of rectal cancer in the Changhai Hospital from January 2007 to December 2008. Age at diagnosis, gender distribution, symptom, delay in diagnosis, TNM stage, and grade of differentiation were recorded and analyzed. The importance of digital examination and colonoscopy were addressed. RESULTS: Two hundred and seventy-one(47.7%) out of 568 patients were misdiagnosed for iatrogenic reasons. Rectal cancer patients who presented hematochezia were more likely to be misdiagnosed. There were 110 cases of stage III(40.6%) and 68 cases of stage IV(12.5%) in patients who were misdiagnosed, which was significantly higher than those who were diagnosed correctly(P<0.05). Patients under 40 years old were more likely to be misdiagnosed, and their correct diagnosis was often delayed longer and the tumors were in more advanced stage as compared to the older groups(P<0.05). CONCLUSIONS: The misdiagnosis rate of rectal cancer is high. Tumor stage of patients misdiagnosed is significantly more advanced than those who are correctly diagnosed. Digital examination and colonoscopy should be emphasized, especially for patients under the age of 40.