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The incidence of early-onset colorectal cancer (EOCRC) has increased significantly worldwide. Uncovering biomarkers that are unique to EOCRC is of great importance to facilitate the prevention and detection of this growing cancer subtype. Although efforts have been made in the data curation about CRC, there is no integrated platform that gives access to data specifically related to young CRC patients. Here, we constructed a user-friendly open integrated resource called CRCDB (URL: http://crcdb-hust.com) which contains multi-omics data of 785 EOCRC, 4898 late-onset CRCs (LOCRC), and 1110 normal control samples from tissue, whole blood, platelets, and serum exosomes. CRCDB manages the differential analysis, survival analysis, co-expression analysis, and immune cell infiltration comparison analysis results in different CRC groups. Meta-analysis results were also provided for users for further data interpretation. Using the resource in CRCDB, we identified that genes associated with the metabolic process were less expressed in EOCRC patients, while up regulated genes most associated with the mitosis process might play an important role in the molecular pathogenesis of LOCRC. Survival-related genes were most enriched in oxidoreduction pathways in EOCRC while in immune-related pathways in LOCRC. With all the data gathered and processed, we anticipate that CRCDB could be a practical data mining platform to help explore potential applications of omics data and develop effective prevention and therapeutic strategies for the specific group of CRC patients.

Abstract. Background:. Findings on the association of genetic factors and colorectal cancer (CRC) survival are limited and inconsistent, and revealing the mechanism underlying their prognostic roles is of great importance. This study aimed to explore the relationship between functional genetic variations and the prognosis of CRC and further reveal the possible mechanism. Methods:. We first systematically performed expression quantitative trait locus (eQTL) analysis using The Cancer Genome Atlas (TCGA) dataset. Then, the Kaplan-Meier analysis was used to filter out the survival-related eQTL target genes of CRC patients in two public datasets (TCGA and GSE39582 dataset from the Gene Expression Omnibus database). The seven most potentially functional eQTL single nucleotide polymorphisms (SNPs) associated with six survival-related eQTL target genes were genotyped in 907 Chinese CRC patients with clinical prognosis data. The regulatory mechanism of the survival-related SNP was further confirmed by functional experiments. Results:. The rs71630754 regulating the expression of endoplasmic reticulum aminopeptidase 1 (ERAP1) was significantly associated with the prognosis of CRC (additive model, hazard ratio [HR]: 1.43, 95% confidence interval [CI]: 1.08-1.88, P = 0.012). The results of dual-luciferase reporter assay and electrophoretic mobility shift assay showed that the A allele of the rs71630754 could increase the binding of transcription factor 3 (TCF3) and subsequently reduce the expression of ERAP1. The results of bioinformatic analysis showed that lower expression of ERAP1 could affect the tumor immune microenvironment and was significantly associated with severe survival outcomes. Conclusion:. The rs71630754 could influence the prognosis of CRC patients by regulating the expression of the immune-related gene ERAP1. Trial Registration:. No. NCT00454519 (https://clinicaltrials.gov/)

Background: Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths worldwide. However, due to the heterogeneity of CRC, the clinical therapy outcomes differ among patients. There is a need to identify predictive biomarkers to efficiently facilitate CRC treatment and prognosis.Methods: The expression profiles from Gene Expression Omnibus (GEO) database were used to identify cancer hallmarks associated with CRC outcomes. An accurate gene signature based on the prognosis related cancer hallmarks was further constructed.Results: Hypoxia was identified to be the primary factor that could influence CRC outcomes. Sixteen hypoxia-related genes were selected to construct a risk gene signature (HGS) associated with individuals’ prognosis, which was validated in three independent cohorts. Further, stromal and immune cells in tumor microenvironment (TME) were found to be associated with hypoxia. Finally, among the 16 hypoxia-related genes, six genes (DCBLD2, PLEC, S100A11, PLAT, PPAP2B and LAMC2) were identified as the most attributable ones to drug resistance.Conclusion: HGS can accurately predict CRC prognosis. The expression of the drug resistance-related genes is critical in CRC treatment decision-making.

Abstract Pancreatic cancer is one of the deadliest malignancies with few early detection tests or effective therapies. PI3K‐AKT signaling is recognized to modulate cancer progression. We previously identified that a genetic variant in PKN1 increased pancreatic cancer risk through the PKN1/FAK/PI3K/AKT pathway. In order to investigate the associations between genetic variations in that pathway and pancreatic cancer prognosis, we conducted a two‐stage survival analysis in a total of 547 Chinese pancreatic cancer patients. Consequently, a variant, rs13167294 A>C in PIK3R1, was significantly associated with poor survival in both stages and with hazard ratio being 1.32 (95% CI = 1.13‐1.56, P = 0.0007) in the combined analysis. Function annotation and prediction suggested that genetic variants in this locus might affect overall survival of pancreatic cancer patients by regulating PIK3R1 expression.

Background: Epirubicin combined with docetaxel is the cornerstone of neoadjuvant chemotherapy (NAC) for breast cancer. The efficacy of NAC for luminal A breast cancer patients is very limited, and single nucleotide polymorphism is one of the most important factors that influences the efficacy. Our study is aimed to explore genetic markers for the efficacy of epirubicin combined with docetaxel for NAC in patients with luminal A breast cancer.Methods: A total of 421 patients with two stages of luminal A breast cancer were enrolled in this study from 2 centers. Among them 231 patients were included in the discovery cohort and 190 patients are in the replication cohort. All patients received epirubicin 75 mg/m2 and docetaxel 75 mg/m2 on day 1, in a 21-day cycle, a cycle for 2–6 cycles. Before treatment, 2 ml of peripheral blood was collected from each patient to isolate genomic DNA. Fourteen functional variants potentially regulating epirubicin/docetaxel response genes were prioritized by CellMiner and bioinformatics approaches. Moreover, biological assays were performed to determine the effect of genetic variations on response to chemotherapy.Results: The patients carrying rs6484711 variant A allele suffered a poor response to epirubicin and docetaxel for NAC (OR = 0.37, 95% CI: 0.18–0.74, P = 0.005) in combined stage. Moreover, expression quantitative trait loci (eQTL) analyses and luciferase reporter assays revealed that rs6484711 A allele significantly increased the expression of ABTB2. Subsequent biological assays illustrated that upregulation of ABTB2 significantly reduced the apoptosis rate of breast cancer cells and enhanced the chemo-resistance to epirubicin.Conclusions: Our study demonstrated rs6484711 polymorphism regulating ABTB2 expression might predict efficacy to epirubicin based NAC in luminal A breast cancer patients. These results provided valuable information about potential role of genetic variations in individualized chemotherapy.

Pancreatic ductal adenocarcinoma is a lethal human cancer with a poor 5-year overall survival rate. Here the authors perform an exome-wide analysis in a cohort of PDAC patients to identify three novel missense variants in PKN1, DOK2, and APOB genes, that are associated with PDAC risk.

Background: Genome-wide association studies (GWAS) have identified dozens of loci associated with colon and rectal adenocarcinoma risk. As tissue-specific super-enhancers (SE) play important roles in tumorigenesis, we systematically investigate SEs and inner variants in established GWAS loci to decipher the underlying biological mechanisms. Methods: Through a comprehensive bioinformatics analysis on multi-omics data, we screen potential single-nucleotide polymorphisms (SNP) in cancer-specific SEs, and then subject them to a two-stage case-control study containing 4,929 cases and 7,083 controls from the Chinese population. A series of functional assays, including reporter gene assays, electrophoretic mobility shift assays (EMSA), CRISPR-Cas9 genome editing, chromosome conformation capture (3C) assays, and cell proliferation experiments, are performed to characterize the variant's molecular consequence and target genes. Results: The SNP rs11064124 in 12p13.31 is found significantly associated with the risk of colon and rectal adenocarcinoma with an odds ratio (OR) of 0.87 [95% confidence interval (CI), 0.82-0.92, P = 8.67E-06]. The protective rs11064124-G weakens the binding affinity with vitamin D receptor (VDR) and increases the enhancer's activity and interactions with two target genes' promoters, thus coactivating the transcription of CD9 and PLEKHG6, which are both putative tumor suppressor genes for colon and rectal adenocarcinoma. Conclusions: Our integrative study highlights an SE polymorphism rs11064124 and two susceptibility genes CD9 and PLEKHG6 in 12p13.31 for colon and rectal adenocarcinoma. Impact: These findings suggest a novel insight for genetic pathogenesis of colon and rectal adenocarcinoma, involving transcriptional coactivation of diverse susceptibility genes via the SE element as a gene regulation hub. [ABSTRACT FROM AUTHOR]

Background: Telomere dysfunction triggers cellular senescence and constitutes a driving force for cancer initiation. Genetic variants in genes involved in telomere maintenance may contribute to colorectal cancer susceptibility. Methods: In this study, we firstly captured germline mutations in 192 patients with colorectal cancer by sequencing the coding regions of 13 core components implicated in telomere biology. Five potential functional variants were then genotyped and assessed in a case-control set with 3,761 colorectal cancer cases and 3,839 healthy controls. The promising association was replicated in additional 6,765 cases and 6,906 controls. Functional experiments were used to further clarify the potential function of the significant variant and uncover the underlying mechanism in colorectal cancer development. Results: The two-stage association studies showed that a rare missense variant rs149418249 (c.C1520T and p.P507L) in the 11th exon of TPP1 (also known as ACD, gene ID 65057) was significantly associated with colorectal cancer risk with the ORs being 2.90 [95% confidence interval (CI), 1.04-8.07; P = 0.041], 2.50 (95% CI, 1.04-6.04; P = 0.042), and 2.66 (95% CI, 1.36-5.18; P = 0.004) in discovery, replication, and the combined samples, respectively. Further functional annotation indicated that the TPP1 P507L substitution interrupted TPP1-TIN2 interaction, impaired telomerase processivity, and shortened telomere length, which subsequently facilitated cell proliferation and promoted colorectal cancer development. Conclusions: A rare variant P507L in TPP1 confers increased risk of colorectal cancer through interrupting TPP1-TIN2 interaction, impairing telomerase processivity, and shrinking telomere length. Impact: These findings emphasize the important role of telomere dysfunction in colorectal cancer development, and provide new insights about the prevention of this type of cancer. [ABSTRACT FROM AUTHOR]

The gender disparity observed in the incidence of hepatocellular carcinoma (HCC) suggests an important role of estrogens in HCC pathogenesis. In this study, we conducted a case-control study to investigate whether breast cancer riskassociated single nucleotide polymorphisms (SNPs) located at estrogens loci identified by genome-wide association studies (GWASs) also predispose to HCC in a Chinese population. Three candidate SNPs at 6q25.1 were genotyped in 2025 HCC cases and 2032 healthy controls. Differential expression analyses and expression quantitative trait loci (eQTL) analyses were conducted to further explore the potential function of significant SNPs and genes they reside in. Two of the three candidate SNPs (rs9383951 and rs9485372) were observed to be significantly associated with HCC risk. Under a dominant model, the odds ratios (OR) for rs9383951 and rs9485372 were 1.28 (95% CI: 1.10-1.49, P = 0.002) and 1.34 (95% CI: 1.17-1.53, P = 2.75 × 10-5), respectively. We also found a significant accumulative effect of these two SNPs and there was a gradual increase in OR with a greater number of hazard genotypes. Moreover, the association between rs9383951 and HCC risk was specific in males. Lower ESR1 and TAB2 expressions were investigated in hepatic tumor tissues than adjacent normal tissues. We found a significant association between rs9383951 and ESR1 expression (P = 0.047). Besides, ESR1 expression was significantly correlated with the expression of TAB2. Taken together, our study identified two genetic variants at 6q25.1 newly associated with HCC risk, suggesting ESR1 and estrogen signaling may play a role in mediating susceptibility to HCC in Chinese population. [ABSTRACT FROM AUTHOR]