Hypermethylation of APC2 Is a Predictive Epigenetic Biomarker for Chinese Colorectal Cancer

Methylation of APC2, NR3C1, and DRD2 gene promoters in turkish patients with tobacco use disorder

Background

Many studies have investigated the association of the methylation of gene and tobacco use disorders (TUD), but results remain ambiguous.

Aims

This study evaluated the relationship between methylation of Adenomatosis Polyposis Coli (APC), Nuclear Receptor subfamily 3 group C member 1 (NR3C1), Dopamine D2 receptor (DRD2) gene promoters, and its effect on TUD.

Subjects and Methods

We recruited 154 active smokers and 111 healthy non-smoker controls. PCR based methods on genomic DNA characterized the methylation of APC2, NR3C1, and DRD2 gene promoters.

Results

We have found a significant difference in methylation of APC2 for TUD compared to healthy controls (P < 0.001). The partial methylation ratio was about an eight-fold increase in smokers compared to healthy controls. NR3C1 methylation was slightly higher in TUD patients compared to the control group, but the difference was not significant between the two groups (%95.33 vs. 91.08, P = 0.269). DRD2 methylation ratio was not significant between TUD patients and healthy control groups (P = 0.894).

Conclusion

We think that it is important to detect APC2 methylated cases earlier and to advise them to quit smoking.

FOXO4 Inhibits the Migration and Metastasis of Colorectal Cancer by Regulating the APC2/β-Catenin Axis

Objective: Adenomatous polyposis coli 2 (APC2) is a colorectal cancer (CRC) tumor-suppressor gene. The progression of several kinds of cancer is closely associated with Forkhead box O4 (FOXO4). However, the function of FOXO4 in CRC is unclear. This study focused on the role of FOXO4 and the relationship between FOXO4 and APC2 in CRC migration and metastasis.

Methods: The expressions of FOXO4, APC2, and p(S37)-β-catenin were detected in CRC tissues by immunohistochemistry, and their correlation was analyzed using the Spearman coefficient. Chromatin immunoprecipitation was used to test whether FOXO4 binds and regulates APC2 as a transcription factor. Either FOXO4 overexpression or APC2 knockdown was performed in CRC cell lines. The roles of FOXO4 and APC2 were investigated in CRC migration and metastasis.

Results: FOXO4 was downregulated in CRC tissues compared with normal tissues and positively correlated with APC2 and p(S37)-β-catenin. FOXO4 could combine the promoter region of APC2 to upregulate its expression and increase the phosphorylated degradation of β-catenin. Stemness genes (CD133, ABCG1, and SOX2) were inhibited by FOXO4 overexpression in SW620 and HCT116 cell lines. Overexpressed FOXO4 suppressed epithelial–mesenchymal transition and the migration of CRC cell lines and metastasis of HCT116 in both the spleen and liver of nude mice, which was reversed by APC2 knockdown.

Conclusion: This research demonstrates that overexpressed FOXO4 inhibits the migration and metastasis of CRC cells by enhancing the APC2/β-catenin axis, suggesting that FOXO4 is a potential therapeutic target of CRC.

Mutations and mechanisms of WNT pathway tumour suppressors in cancer

Mutation-induced activation of WNT-β-catenin signalling is a frequent driver event in human cancer. Sustained WNT-β-catenin pathway activation endows cancer cells with sustained self-renewing growth properties and is associated with therapy resistance. In healthy adult stem cells, WNT pathway activity is carefully controlled by core pathway tumour suppressors as well as negative feedback regulators. Gene inactivation experiments in mouse models unequivocally demonstrated the relevance of WNT tumour suppressor loss-of-function mutations for cancer growth. However, in human cancer, a far more complex picture has emerged in which missense or truncating mutations mediate stable expression of mutant proteins, with distinct functional and phenotypic ramifications. Herein, we review recent advances and challenges in our understanding of how different mutational subsets of WNT tumour suppressor genes link to distinct cancer types, clinical outcomes and treatment strategies.

Regulation of Wnt receptor activity: Implications for therapeutic development in colon cancer

Hyperactivation of Wnt/β-catenin (canonical) signaling in colorectal cancers (CRCs) was identified in the 1990s. Most CRC patients have mutations in genes that encode components of the Wnt pathway. Inactivating mutations in the adenomatous polyposis coli (APC) gene, which encodes a protein necessary for β-catenin degradation, are by far the most prevalent. Other Wnt signaling components are mutated in a smaller proportion of CRCs; these include a FZD-specific ubiquitin E3 ligase known as ring finger protein 43 that removes FZDs from the cell membrane. Our understanding of the genetic and epigenetic landscape of CRC has grown exponentially because of contributions from high-throughput sequencing projects such as The Cancer Genome Atlas. Despite this, no Wnt modulators have been successfully developed for CRC-targeted therapies. In this review, we will focus on the Wnt receptor complex, and speculate on recent discoveries about ring finger protein 43regulating Wnt receptors in CRCs. We then review the current debate on a new APC-Wnt receptor interaction model with therapeutic implications.

Low expression of adenomatous polyposis coli 2 correlates with aggressive features and poor prognosis in colorectal cancer

Currently, there are no relevant findings on the diagnostic and prognostic roles of adenomatous polyposis coli 2 (APC2) in colorectal cancer (CRC). This study investigated the clinical value of APC2 dysregulation in the prognosis of CRC. Immunohistochemical scores obtained from tissue microarrays were used to quantify the expression of APC2 protein in 201 CRC tissues and 139 adjacent normal tissues. A chi-squared test was performed to analyze the association between APC2 expression and various clinical characteristics. Differences in 5-year survival between groups were analyzed. A receiver operating characteristic (ROC) curve was generated to investigate the potential association between APC2 and CRC diagnosis. Compared with adjacent normal tissues, APC2 was downregulated in CRC tissues (P = 0.0004). Survival analyses revealed that CRC patients with high APC2 expression (96.74%) obtained better 5-year survival rates than those with low APC2 expression (88.07%). CRC patients with low APC2 expression exhibited obvious lymphovascular invasion (P = 0.010), lymph node metastasis (P = 0.007), and high tumor node metastasis (TNM) stage (P = 0.007). Furthermore, ROC curves confirmed that APC2 was associated with lymphovascular invasion (P = 0.004), lymph node metastasis (P = 0.002), and TNM staging (P = 0.002). In summary, low APC2 expression in CRC tissues was associated with poor prognosis and may be a useful biomarker for the prognosis and clinical classification of CRC.

Identification of a Multi-RNA-Type-Based Signature for Recurrence-Free Survival Prediction in Patients with Uterine Corpus Endometrial Carcinoma

Uterine corpus endometrial carcinoma (UCEC) is one of the leading causes of death from gynecological cancer due to the high recurrence rate. A recent study indicated that molecular biomarkers can enhance the recurrence prediction power if they were integrated with clinical information. In this study, we attempted to identify a new multi-RNA-type-based molecular biomarker for predicting the recurrence risk and recurrence-free survival (RFS). Matched mRNA (including lncRNA) and miRNA RNA-sequencing data from 463 UCEC patients (n = 75, recurrent; n = 388, non-recurrent) were downloaded from The Cancer Genome Atlas database. LASSO (least absolute shrinkage and selection operator) analysis was used to screen the optimal combination of prognostic RNAs and then the risk score model was constructed. Moreover, the molecular mechanisms of prognostic RNAs were explored by establishing various interaction networks based on corresponding predictive databases. A multi-RNA-type-based signature (including three miRNAs: hsa-miR-6511b, hsa-miR-184, hsa-miR-4461; three lncRNAs: ENO1-IT1, MCCC1-AS1, AATBC; and 7 mRNAs: EPPK1, ASB9, BDNF, CYP11A1, ECEL1, EN2, F13A1) was developed for the prediction of RFS. The risk scoring system established by these signature genes was effective for the discrimination of the 5-year RFS in the high-risk from low-risk patients in the training [an area under the receiver operating characteristic curve (AUC) = 0.960], validation (AUC = 0.863), and entire datasets (AUC = 0.873). This risk score model was also proved to be a more excellent, independent prognostic discriminator than the single-RNA-type (overall AUC: 0.947 vs. 0.677, lncRNAs; 0.709, miRNAs; 0.899, mRNAs) and clinical staging (overall AUC: 0.947 vs. 0.517). Furthermore, the downstream mechanisms for some prognostic miRNAs or lncRNAs (HAND2-AS1-hsa-miR-6511b-APC2, PAX8-AS1-hsa-miR-4461-TNIK and MCCC1-AS1/ENO1-IT1-TNIK) were newly predicted based on the coexpression or competitive endogenous RNA theories. In conclusion, our findings may provide novel biomarkers for recurrence prediction and targets for treatment of UCEC.

Plasma Inter-Alpha-Trypsin Inhibitor Heavy Chains H3 and H4 Serve as Novel Diagnostic Biomarkers in Human Colorectal Cancer

Objective

Inter-alpha-trypsin inhibitor heavy chain H3 (ITIH₃) and inter-alpha-trypsin inhibitor heavy chain H4 (ITIH₄) are heavy chains of protein members belonging to the ITI family, which was associated with inflammation and carcinogenesis. However, the diagnostic value of ITIH₃ and ITIH₄ in human colorectal cancer (CRC) remains unknown.

Methods

In total, 101 CRC patients and 156 healthy controls were enrolled. The concentrations of ITIH₃ and ITIH₄ proteins in plasma samples of participants were assessed using enzyme-linked immunosorbent assay. ITIH₃ and ITIH₄ expressions in human CRC tissues were additionally assessed via immunohistochemical staining (IHC). Receiver operating characteristic (ROC) was applied to estimate the diagnostic power of the two proteins, and the net reclassification improvement (NRI) was adopted to evaluate the incremental predictive ability of ITIH₃/ITIH₄ when added to the tissue inhibitor of metalloproteinase-1 (TIMP-1).

Results

The plasma concentration of ITIH₃ in CRC patients (median: 4.370 μg/mL; range: 2.152–8.170 μg/mL) was significantly lower than that in healthy subjects (median: 4.715 μg/mL; range: 2.665–10.257 μg/mL; p < 0.001), while the ITIH₄ plasma level in subjects with CRC (median: 0.211 μg/mL; range: 0.099–0.592 μg/mL) was markedly increased relative to that in the control group (median: 0.134 μg/mL; range: 0.094–0.460 μg/mL, p < 0.001). Consistently, IHC score assessment showed a dramatic reduction in ITIH₃ expression and, conversely, upregulation of ITIH₄ in colorectal carcinoma specimens relative to adjacent normal colorectal tissues (p < 0.001 in both cases). The area under the curve (AUC) of the ROC for ITIH₄ (AUC = 0.801, 95% CI: 0.745–0.857) was higher than that for ITIH₃ (AUC = 0.638, 95% CI: 0.571–0.704, both p values < 0.001). The AUC of the ROC for combined ITIH₃ and ITIH₄ was even higher than that for carcinoembryonic antigen. NRI results showed that combining ITIH₃ and ITIH₄ with TIMP-1 significantly improved diagnostic accuracy (NRI = 17.12%, p = 0.002) for CRC patients compared to TIMP-1 alone.

Conclusions

Circulating ITIH₃ and ITIH₄ levels are associated with carcinogenesis in CRC, supporting their potential diagnostic utility as surrogate biomarkers for colorectal cancer detection.