IGSF6 is a novel biomarker to evaluate immune infiltration in mismatch repair-proficient colorectal cancer.

Immunotherapy has dramatically changed the landscape of treatment for colorectal cancer (CRC), but currently lack of effective predictive biomarker, especially for tumors with mismatch repair (MMR) proficiency. The response of immunotherapy is associated with the cell-cell interactions in tumor microenvironment, encompassing processes such as cell-cell recognition, binding, and adhesion. However, the function of immunoglobulin superfamily (IGSF) genes in tumor immune microenvironment remains uncharacterized. This study quantified the immune landscape by leveraging a gene expression matrix from publicly accessible databases. The associations between IGSF6 gene expression and immune cell infiltration were assessed. The expression levels of IGSF6, CD8+ T cells, CD4+ T cells and CD68+ macrophage cells in cancer tissues from CRC patients and CRC cell lines were evaluated. IGSF6 was more highly expressed in CRC tumor tissues than adjacent normal tissues. And IGSF6 was significantly correlated with immune cell infiltration in MMR-proficient patients. Remarkably, MMR-proficient patients with high IGSF6 expression showed more sensitive to immunotherapy and chemotherapy than those with low IGSF6 expression. In summary, IGSF6 could be a novel biomarker to evaluate immune infiltration and predict therapeutic effect for MMR-proficient CRC.

Identification of an Autophagy-Related Gene Signature for the Prediction of Prognosis in Early-Stage Colorectal Cancer.

Purpose: A certain number of early-stage colorectal cancer (CRC) patients suffer tumor recurrence after initial curative resection. In this context, an effective prognostic biomarker model is constantly in need. Autophagy exhibits a dual role in tumorigenesis. Our study aims to develop an autophagy-related gene (ATG) signature-based on high-throughput data analysis for disease-free survival (DFS) prognosis of patients with stage I/II CRC. Methods: Gene expression profiles and clinical information of CRC patients extracted from four public datasets were distributed to discovery and training cohort (GSE39582), validation cohort (TCGA CRC, n = 624), and meta-validation cohort (GSE37892 and GSE14333, n = 420). Autophagy genes significantly associated with prognosis were identified. Results: Among 655 autophagy-related genes, a 10-gene ATG signature, which was significantly associated with DFS in the training cohort (HR, 2.76[1.56-4.82]; p = 2.06 × 10-4), was constructed. The ATG signature, stratifying patients into high and low autophagy risk groups, was validated in the validation (HR, 2.29[1.15-4.55]; p = 1.5 × 10-2) and meta-validation cohorts (HR, 2.5[1.03-6.06]; p = 3.63 × 10-2) and proved to be prognostic in a multivariate analysis. Functional analysis revealed enrichment of several immune/inflammatory pathways in the high autophagy risk group, where increased infiltration of T regulatory cells (Tregs) and decreased infiltration of M1 macrophages were observed. Conclusion: Our study established a prognostic ATG signature that effectively predicted DFS for early-stage CRC patients. Meanwhile, the study also revealed the possible relationship among autophagy process, immune/inflammatory response, and tumorigenesis.

An 11-gene signature for the prediction of systemic recurrences in colon adenocarcinoma.

BACKGROUND: Prognosis varies among patients within the same colon adenocarcinoma (COAD) stage, indicating the need for reliable molecular markers to enable individualized treatment. This study aimed to investigate gene signatures that can be used for better prognostic prediction of COAD. METHODS: Gene-expression profiles of COAD patients were obtained from the Gene Expression Omnibus database (n = 332) and The Cancer Genome Atlas database (n = 431). The relationship between gene signature and relapse-free survival was analysed in the training set (n = 93) and validated in the internal validation set (n = 94) and external validation sets (n = 145 and 431). RESULTS: Overall, 11 genes (N-myc downstream regulated gene 1 [NDRG1], fms-like tyrosine kinase 1 [FLT1], lipopolysaccharide binding protein [LBP], fatty acid binding protein 4 [FABP4], adiponectin gene [ADIPOQ], angiotensinogen gene [AGT], activin A receptor, type II-like kinase 1 [ACVRL1], CC chemokine ligand 11 [CCL11], cell division cycle 42 [CDC42], T-cell receptor alpha variable 9_2 [TRAV9_2], and proopiomelanocortin [POMC]) were identified by univariable and least absolute shrinkage and selection operator (LASSO) Cox regression analyses. Based on the risk-score model, the patients were grouped into the high-risk or low-risk groups using the median risk score as the cut-off. The area under the curve (AUC) values for 1-, 3-, and 5-year recurrence were 0.970, 0.849, and 0.859, respectively. Patients in the high-risk group had significantly poorer relapse-free survival than did those in the low-risk group. The predictive accuracy of the 11-gene signature was proven in the validation sets. Our gene signature showed better predictive performance for 1-, 3-, and 5-year recurrence than did the other four models. CONCLUSIONS: The 11-gene signature showed good performance in predicting recurrence in COAD. The accuracy of the signature for prognostic classification requires further confirmation.

Effects of Huaier Extract on Ameliorating Colitis-Associated Colorectal Tumorigenesis in Mice.

BACKGROUND: Huaier extract has been a part of traditional Chinese medicine (TCM) for roughly 1600 years and may serve as a potential anti-cancer drug as it is associated with good efficacy and low toxicity. Individuals with inflammatory bowel disease (IBD) are at a higher chance of being diagnosed with colorectal cancer (CRC) and as Huaier extract may potentially influence tumorigenesis, we set out to determine the effect of Huaier extract on colitis-associated CRC. METHODS: The CRC mouse model, established through azoxymethane (AOM) and dextran sulfate sodium (DSS), was administered Huaier extract. Weight loss, colon length, tumor number and tumor size were evaluated macroscopically. Pro-inflammatory cytokine expression and STAT3 phosphorylation were assessed in the colon using ELISA, Western blot and/or immunohistochemistry. RESULTS: Huaier extract improved the severity of colitis-associated tumorigenesis compared with control group, with attenuated weight loss and longer colons. Tumor number, size and load were drastically decreased in mice treated with Huaier. Histological assessment suggested that Huaier could decrease histological injury of the colon tissue. Additionally, Huaier extract treatment led to reduced pro-inflammatory cytokine levels (TNF-α, IL-6, IFN-γ and IL-1ß) and a decrease of STAT3 phosphorylation in colon tissue. Additionally, present findings demonstrated that Huaier extract inhibited cell proliferation and induced apoptosis in CRC cells HCT116 and HCT8. The migration and invasion of CRC cells were markedly inhibited upon exposure to Huaier treatment. The apoptosis-associated protein levels (P53, Bax, Bcl-2, pro-caspase-3 and cleavage caspase-3) showed significant differences after the administration of Huaier extract in HCT116 and HCT8 cells. In vivo, the administration of Huaier extract to mice inhibited tumor growth and yielded a similar profile of apoptotic proteins expression p53, Bcl-2, pro-caspase-3 and cleaved caspase-3 while no significant differences in Bax were observed. Moreover, the ratio of TUNEL-positive/apoptotic cells was markedly increased in the Huaier-treated mice. CONCLUSION: Huaier extract may reduce the IBD-associated tumor development by suppressing pro-inflammatory cytokine levels and STAT3 stimulation.