Integration of pathologic characteristics, genetic risk and lifestyle exposure for colorectal cancer survival assessment.

The development of an effective survival prediction tool is key for reducing colorectal cancer mortality. Here, we apply a three-stage study to devise a polygenic prognostic score (PPS) for stratifying colorectal cancer overall survival. Leveraging two cohorts of 3703 patients, we first perform a genome-wide survival association analysis to develop eight candidate PPSs. Further using an independent cohort with 470 patients, we identify the 287 variants-derived PPS (i.e., PPS287) achieving an optimal prediction performance [hazard ratio (HR) per SD = 1.99, P = 1.76 × 10-8], accompanied by additional tests in two external cohorts, with HRs per SD of 1.90 (P = 3.21 × 10-14; 543 patients) and 1.80 (P = 1.11 × 10-9; 713 patients). Notably, the detrimental impact of pathologic characteristics and genetic risk could be attenuated by a healthy lifestyle, yielding a 7.62% improvement in the 5-year overall survival rate. Therefore, our findings demonstrate the integrated contribution of pathologic characteristics, germline variants, and lifestyle exposure to the prognosis of colorectal cancer patients.

Benzo[a]pyrene exposure affects colorectal cancer susceptibility by regulating ERß-mediated LINC02977 transcription.

Environmental pollutants known as polycyclic aromatic hydrocarbons (PAHs) are produced through the incomplete combustion of organic material. While PAHs have been investigated as genotoxicants, they can also operate through nongenotoxic pathways in estrogen-dependent malignancies, such as breast, cervical and ovarian cancer. However, whether PAHs induce colorectal cancer (CRC) risk through estrogenic effects is still illusive. Here, we systematically investigated the abnormal expression and activation of estrogen receptor beta (ERß) regulated by PAHs in CRC as well as the underlying mechanisms of ERß-mediated CRC risk. Based on the 300 plasma samples from CRC patients and healthy controls detected by GC-MS/MS, we found that the plasma concentrations of benzo[a]pyrene (BaP) were significantly higher in CRC cases than in healthy controls, with significant estrogenic effects. Moreover, histone deacetylase 2 (HDAC2)-induced deacetylation of the promoter decreases ERß expression, which is associated with poor overall survival and advanced tumor stage. The study also revealed that BaP and estradiol (E2) had different carcinogenic effects, with BaP promoting cell proliferation and inhibiting apoptosis, while E2 had the opposite effects. Additionally, this study mapped ERß genomic binding regions by performing ChIP-seq and ATAC-seq and identified genetic variants of rs1411680 and its high linkage disequilibrium SNP rs6477937, which were significantly associated with CRC risk through meta-analysis of two independent Chinese population genome-wide association studies comprising 2,248 cases and 3,173 controls and then validation in a large-scale European population. By integrating data from functional genomics, we validated the regulatory effect of rs6477937 as an ERß binding-disrupting SNP that mediated allele-specific expression of LINC02977 in a long-range chromosomal interaction manner, which was found to be highly expressed in CRC tissues. Overall, this study suggests that the different active effects on ERß by PAHs and endogenous E2 may play a crucial role in the development and progression of CRC and highlights the potential of targeting ERß and its downstream targets for CRC prevention and treatment.

Genetic variants in hypoxia-inducible factor pathway are associated with colorectal cancer risk and immune infiltration.

Hypoxia-inducible factor (HIF) pathway genes influence tumorigenesis and immune status. However, the associations between genetic variants in hypoxia-related genes and colorectal cancer risk and the immune status of hypoxia-associated genes in colorectal cancer have not been systematically characterized. The associations between genetic variants and colorectal cancer risk were evaluated in Chinese, Japanese and European populations using logistic regression analysis. The relationships between target genes and tumour immune infiltration were predicted by Tumour Immune Estimation Resource (TIMER). We found that rs34533650 in EPAS1 was associated with colorectal cancer risk (OR = 1.43, 95% CI = 1.20-1.70, P(FDR) = 8.35 × 10-4 ), and this finding was validated in two independent populations (Japanese: OR = 1.07, 95% CI = 1.01-1.15, p = 3.38 × 10-2 ; European: OR = 1.11, 95% CI = 1.03-1.19, p = 6.04 × 10-3 ). EPAS1-associated genes were enriched in immune-related pathways. In addition, we found that EPAS1 copy number variation (CNV) was associated with the degree of infiltration of immune cells and observed correlations between EPAS1 expression and immune cell infiltration levels in colorectal cancer. These results highlight that genetic variants of hypoxia-related genes play roles in colorectal cancer risk and provide new insight that EPAS1 might be a promising predictor of colorectal cancer susceptibility and immune status.

Causal genetic regulation of DNA replication on immune microenvironment in colorectal tumorigenesis: Evidenced by an integrated approach of trans-omics and GWAS.

The interplay between DNA replication stress and immune microenvironment alterations is known to play a crucial role in colorectal tumorigenesis, but a comprehensive understanding of their association with and relevant biomarkers involved in colorectal tumorigenesis is lacking. To address this gap, we conducted a study aiming to investigate this association and identify relevant biomarkers. We analyzed transcriptomic and proteomic profiles of 904 colorectal tumor tissues and 342 normal tissues to examine pathway enrichment, biological activity, and the immune microenvironment. Additionally, we evaluated genetic effects of single variants and genes on colorectal cancer susceptibility using data from genome-wide association studies (GWASs) involving both East Asian (7062 cases and 195745 controls) and European (24476 cases and 23073 controls) populations. We employed mediation analysis to infer the causal pathway, and applied multiplex immunofluorescence to visualize colocalized biomarkers in colorectal tumors and immune cells. Our findings revealed that both DNA replication activity and the flap structure-specific endonuclease 1 ( FEN1) gene were significantly enriched in colorectal tumor tissues, compared with normal tissues. Moreover, a genetic variant rs4246215 G>T in FEN1 was associated with a decreased risk of colorectal cancer (odds ratio = 0.94, 95% confidence interval: 0.90-0.97, P meta = 4.70 × 10 -9). Importantly, we identified basophils and eosinophils that both exhibited a significantly decreased infiltration in colorectal tumors, and were regulated by rs4246215 through causal pathways involving both FEN1 and DNA replication. In conclusion, this trans-omics incorporating GWAS data provides insights into a plausible pathway connecting DNA replication and immunity, expanding biological knowledge of colorectal tumorigenesis and therapeutic targets.

Genetic Modulation of BET1L Confers Colorectal Cancer Susceptibility by Reducing miRNA Binding and m6A Modification.

Genetic variants in regions encoding 3' untranslated regions (UTR) of mRNA potentially alter miRNA binding affinity and N6-methyladenosine (m6A) levels to affect gene expression. A better understanding of the association of these variants with colorectal cancer susceptibility could facilitate development of cancer prevention and treatment approaches. Here, we analyzed miRNA expression profiles and integrated genetic analyses from 8,533 individuals to evaluate the effects of altered miRNA-binding sites on colorectal cancer risk. The single-nucleotide polymorphism rs11245997 in the BET1L 3'UTR was significantly associated with colorectal cancer risk. The rs11245997 A allele facilitated BET1L expression by disrupting miR-140-3p binding. It also reduced BET1L m6A modification, which upregulated BET1L expression levels through a mechanism mediated by the m6A methyltransferases (METTL14 and WTAP) and the m6A demethylase ALKBH5. Moreover, higher expression of BET1L was associated with advanced tumor stages and poor patient prognosis. Increased BET1L expression promoted growth of colorectal cancer cells in vitro and in vivo, which could be partially rescued with miR-140-3p overexpression. RNA sequencing and pathway analyses indicated that BET1L is associated with the steroid biosynthesis pathway through regulation of HSD17B7, CYP27B1, and COMT. These findings provide insights into the involvement of genetic variants of BET1L in the development and progression of colorectal cancer. SIGNIFICANCE: The integration of miRNA expression profiles and genetic variants identified rs11245997 as a colorectal cancer risk-related variant that reduces miR-140-3p binding and m6A modification, leading to BET1L upregulation to promote colorectal tumorigenesis.

Integrated multi-omics approach to distinct molecular characterization and classification of early-onset colorectal cancer.

Incidence of early-onset colorectal cancer (EOCRC), defined by a diagnosed age under 50 years, is increasing, but its heterogeneous etiologies that differ from general CRC remain undetermined. We initially characterize the genome, epigenome, transcriptome, and proteome of tumors from 79 patients in a Chinese CRC cohort. Data for an additional 126 EOCRC subjects are obtained from the International Cancer Genome Consortium Chinese cohort and The Cancer Genome Atlas European cohort. We observe that early-onset tumors have a high tumor mutation burden; increased DNA repair features by mutational signature 3 and multi-layer pathway enrichments; strong perturbations at effects of DNA methylation and somatic copy-number alteration on gene expression; and upregulated immune infiltration as hot tumors underlying immunophenotypes. Notably, LMTK3 exhibits ancestral mutation disparity, potentially being a functional modulator and biomarker that drives molecular alterations in EOCRC development and immunotherapies. This integrative omics study provides valuable knowledge for precision oncology of CRC.

Metal Exposure Promotes Colorectal Tumorigenesis via the Aberrant N6-Methyladenosine Modification of ATP13A3.

Element contamination, including that from heavy metals, is associated with gastrointestinal tumorigenesis, but the effects and mechanisms of crucial element exposure associated with colorectal cancer remain unclear. We profiled 56 elements by ICP-MS and used logistic regression, LASSO, BKMR, and GAM to identify colorectal cancer-relevant elements. A series of biochemical experiments were performed to demonstrate the cytotoxicity and the mechanisms of malignant transformation after metal exposure. Using an elementomics approach, we first found that the metal thallium (Tl) was positively correlated with many toxic metals and was associated with a significantly increased risk of colorectal cancer. Acute exposure to Tl induced cytotoxicity and cell death by accelerating the generation of reactive oxygen species and DNA damage. Chronic exposure to Tl led to the inhibition of cell death and thereby induced the malignant transformation of normal colon cells and xenograft tumor formation in nude mice. Furthermore, we describe the first identification of a significant metal quantitative trait locus for the novel colorectal cancer susceptibility locus rs1511625 near ATP13A3. Mechanistically, Tl increased the level of aberrant N6-methyladenosine (m6A) modification of ATP13A3 via the METLL3/METTL14/ALKBH5-ATP13A3 axis to promote colorectal tumorigenesis. This study provides a basis for the development of public health strategies for reducing metal exposure among populations at high risk for colorectal cancer.

Prognostic evaluation of polygenic risk score underlying pan-cancer analysis: evidence from two large-scale cohorts.

BACKGROUND: Polygenic risk score (PRS) has been demonstrated to be effective in identifying individuals at high risk of developing cancer, but its prognostic value remains unclear. METHODS: We constructed site-specific PRSs by aggregating the risk effect of independent variants derived from previous genome-wide association studies (GWASs) across 17 cancer types. The Cox proportional hazards model was used to evaluate the association of each PRS with cancer survival, leveraging data from two prospective European cohorts, namely the UK Biobank involving 19,628 incident cases and The Cancer Genome Atlas involving 7079 prevalent cases. The combined PRS (CPRS), determined by merging site-specific PRSs, was further used to assess the prognostic effect of PRS on overall cancer in a sex-specific manner. FINDINGS: We discovered that the cancer risk-related PRS was associated with neither overall survival (OS) nor cancer-specific survival (CSS) of each site-specific cancer with an underlying false discovery rate (FDR) P > 0.05, as evidenced by consistent findings from the two cohorts. Furthermore, the fixed-effect meta-analysis of the two cohorts provided no evidence to support for an association between CPRS and overall cancer survival in both males [OS: hazard ratio (HR)meta = 1.00, Pmeta = 0.760; CSS: HRmeta = 1.01, Pmeta = 0.447] and females (OS: HRmeta = 0.97, Pmeta = 0.067; CSS: HRmeta = 0.96, Pmeta = 0.054). Similar results were observed across multiple sensitivity analyses. INTERPRETATION: Our findings indicate that the risk-specific PRS might not be a clinically useful tool in cancer prognosis prediction and further studies focusing on the development of polygenic prognostic score are warranted. FUNDING: This project was funded by the National Natural Science Foundation of China (82173601 and 82073631), and Priority Academic Program Development of Jiangsu Higher Education Institutions (Public Health and Preventive Medicine).

Risk assessment for colorectal cancer via polygenic risk score and lifestyle exposure: a large-scale association study of East Asian and European populations.

BACKGROUND: The genetic architectures of colorectal cancer are distinct across different populations. To date, the majority of polygenic risk scores (PRSs) are derived from European (EUR) populations, which limits their accurate extrapolation to other populations. Here, we aimed to generate a PRS by incorporating East Asian (EAS) and EUR ancestry groups and validate its utility for colorectal cancer risk assessment among different populations. METHODS: A large-scale colorectal cancer genome-wide association study (GWAS), harboring 35,145 cases and 288,934 controls from EAS and EUR populations, was used for the EAS-EUR GWAS meta-analysis and the construction of candidate EAS-EUR PRSs via different approaches. The performance of each PRS was then validated in external GWAS datasets of EAS (727 cases and 1452 controls) and EUR (1289 cases and 1284 controls) ancestries, respectively. The optimal PRS was further tested using the UK Biobank longitudinal cohort of 355,543 individuals and ultimately applied to stratify individual risk attached by healthy lifestyle. RESULTS: In the meta-analysis across EAS and EUR populations, we identified 48 independent variants beyond genome-wide significance (P < 5 × 10-8) at previously reported loci. Among 26 candidate EAS-EUR PRSs, the PRS-CSx approach-derived PRS (defined as PRSCSx) that harbored genome-wide variants achieved the optimal discriminatory ability in both validation datasets, as well as better performance in the EAS population compared to the PRS derived from known variants. Using the UK Biobank cohort, we further validated a significant dose-response effect of PRSCSx on incident colorectal cancer, in which the risk was 2.11- and 3.88-fold higher in individuals with intermediate and high PRSCSx than in the low score subgroup (Ptrend = 8.15 × 10-53). Notably, the detrimental effect of being at a high genetic risk could be largely attenuated by adherence to a favorable lifestyle, with a 0.53% reduction in 5-year absolute risk. CONCLUSIONS: In summary, we systemically constructed an EAS-EUR PRS to effectively stratify colorectal cancer risk, which highlighted its clinical implication among diverse ancestries. Importantly, these findings also supported that a healthy lifestyle could reduce the genetic impact on incident colorectal cancer.

Genetic variants in RNA m5 C modification genes associated with survival and chemotherapy efficacy of colorectal cancer.

BACKGROUND: Colorectal cancer is one of the most common malignant digestive tract tumors with a poor prognosis. RNA 5-methylcytosine (m5 C) is an important posttranscriptional widespread modification involved in many biological processes. However, the association between genetic variations of m5 C modification genes and the prognostic value of colorectal cancer remains unclear. METHODS: We investigated the association between candidate single nucleotide polymorphisms (SNPs) in 13 m5 C modification genes and colorectal cancer overall survival (OS) after chemotherapy by the Cox regression model. The combined effect of selected SNPs on OS, progression-free survival (PFS), and disease control rate (DCR) was assessed by the number of risk alleles (NRA). The GTEx and TCGA database were used to perform expression qualitative trait locus (eQTL) analysis. RESULTS: We identified that two SNPs in YBX1 were associated with OS after chemotherapy (HR = 1.43, p = 0.001 for rs10890208; HR = 1.36, p = 0.025 for rs3862218). A striking dose-response effect between NRA and OS after chemotherapy was found (ptrend  = 0.002). The DCR of patients receiving oxaliplatin chemotherapy in the 3-4 NRA group was markedly reduced in comparison to that in the 0-2 NRA group (OR = 1.49, p = 0.036). Moreover, YBX1 mRNA expression was significantly overexpressed in tumor tissues (p < 0.05) in the TCGA database, and eQTL analysis demonstrated that the two SNPs were associated with YBX1 (p = 0.003 for rs10890208 and p = 0.024 for rs3862218). CONCLUSION: Our study indicates that genetic variants in m5 C modification genes may mediate changes in YBX1 mRNA levels and affect the chemotherapeutic efficacy of colorectal cancer patients.

SUMMER: a Mendelian randomization interactive server to systematically evaluate the causal effects of risk factors and circulating biomarkers on pan-cancer survival.

Genome-wide association studies (GWASs) underlying case-control design have uncovered hundreds of genetic loci involved in tumorigenesis and provided rich resources for identifying risk factors and biomarkers associated with cancer susceptibility. However, the application of GWAS in determining the genetic architecture of cancer survival remains unestablished. Here, we systematically evaluated genetic effects at the genome-wide level on cancer survival that included overall survival (OS) and cancer-specific survival (CSS), leveraging data deposited in the UK Biobank cohort of a total of 19 628 incident patients across 17 cancer types. Furthermore, we assessed the causal effects of risk factors and circulating biomarkers on cancer prognosis via a Mendelian randomization (MR) analytic framework, which integrated cancer survival GWAS dataset, along with phenome-wide association study (PheWAS) and blood genome-wide gene expression/DNA methylation quantitative trait loci (eQTL/meQTL) datasets. On average, more than 10 traits, 700 genes, and 4,500 CpG sites were prone to cancer prognosis. Finally, we developed a user-friendly online database, SUrvival related cancer Multi-omics database via MEndelian Randomization (SUMMER; http://njmu-edu.cn:3838/SUMMER/), to help users query, browse, and download cancer survival results. In conclusion, SUMMER provides an important resource to assist the research community in understanding the genetic mechanisms of cancer survival.

Exosomal circLPAR1 functions in colorectal cancer diagnosis and tumorigenesis through suppressing BRD4 via METTL3-eIF3h interaction.

BACKGROUND: Exosomes have emerged as vital biomarkers of multiple cancers and contain abundant circular RNAs (circRNAs). However, the potential for exosomal circRNAs to be used in diagnostics and their molecular mechanism of action in colorectal cancer (CRC) remain unclear. METHODS: CRC-specific exosomal circRNAs were identified by RNA sequencing, exoRBase database and a tissue microarray. The diagnostic performance of plasma exosomal circRNAs was evaluated among cancer-free controls, precancer individuals, CRC patients, and patients with other types of cancer. The corresponding biological functions were mainly assessed using circRNA pull-down, proteomic analysis, and RNA immunoprecipitation assay underlying cellular and mouse models. RESULTS: CircLPAR1 was encapsulated in exosomes with high stability and detectability, and its expression in plasma exosomes was remarkably decreased during CRC development but recovered after surgery. Exosomal circLPAR1 showed cancer specificity in CRC diagnosis and increased the diagnostic performance to an area under the receiver operating characteristic curve of 0.875, as determined by analysing its performance in combination with common clinical biomarkers CEA and CA19-9. Additionally, circLPAR1 was downregulated in CRC tissues and was associated with overall survival. Mechanistically, exosomal circLPAR1 was internalized by CRC cells, and it suppressed tumor growth, likely because exosomal circLPAR1 directly bound with eIF3h specifically suppressed the METTL3-eIF3h interaction, decreasing the translation of oncogene BRD4. CONCLUSIONS: This comprehensive study highlights plasma exosomal circLPAR1 as a promising predictor in CRC diagnosis and describes its biological regulation of colorectal tumorigenesis. This study provides a new perspective on early diagnosis in the clinic and pathogenesis in disease development.

Genome-Wide Association Analyses Identify CATSPERE as a Mediator of Colorectal Cancer Susceptibility and Progression.

Genome-wide association studies (GWAS) have revealed numerous genetic loci associated with colorectal cancer risk, but the mechanisms underlying these loci have not been comprehensively elucidated. In this study, we performed a GWAS meta-analysis with a two-stage replication strategy by combining eight colorectal cancer cohorts encompassing 7,186 cases and 8,512 controls in Chinese populations, accompanied by an evaluation encompassing 29,832 cases and 406,694 controls in European populations. The genetic variant rs505706 A>G, located at chr1q44 in the upstream region of catsper channel auxiliary subunit epsilon (CATSPERE), was associated with colorectal cancer risk and exhibited genome-wide significance (OR, 0.73; 95% confidence interval, 0.67-0.80; P = 9.75 × 10-12). Cell line and animal models were applied to assess the biological function of the genetic risk variant and the corresponding susceptibility gene. Genetically, the G allele of rs505706 resulted in long-range regulatory effects, reducing the binding affinity of POU2F1 for the CATSPERE promoter and thus abolishing the inhibitory effect of POU2F1 on CATSPERE transcription. Phenotypically, CATSPERE upregulation attenuated tumor growth in both colorectal cancer cells and xenograft models. Mechanistically, CATSPERE promoted calcium ion influx and apoptotic pathway activity. In zebrafish models, CATSPERE exerted pleiotropic effects, enhancing the progression of colorectal cancer. Collectively, these findings highlight a colorectal cancer susceptibility locus that acts to remotely modulate the activity of CATSPERE, a gene that mediates multiple functions involved in colorectal tumorigenesis and progression. SIGNIFICANCE: A GWAS meta-analysis identifies a novel susceptibility locus harboring a genetic risk variant that mediates pleiotropic biological effects in colorectal tumorigenesis and progression.

Assessment of the Diagnostic Efficiency of a Liquid Biopsy Assay for Early Detection of Gastric Cancer.

Importance: Noninvasive detection of early-stage disease is a key strategy for reducing gastric cancer (GC)-associated patient mortality. Objective: To establish a novel, noninvasive, microRNA (miRNA)-based signature for the early detection of GC using a comprehensive biomarker discovery approach with retrospective and prospective validation. Design, Setting, and Participants: This diagnostic study was conducted in 4 phases using publicly available genome sequences and tissue samples from patients at an academic medical center in Japan, and validated with retrospective multicenter cohorts of patients with GC. Three tissue miRNA data sets were used to identify a miRNA signature that discriminated GC vs normal tissues. The robustness of this signature was assessed in serum from 2 retrospective cohorts of patients with GC. A risk-scoring model was derived, then the performance of the miRNA signature was evaluated in a prospective cohort of patients with GC. The robustness of the miRNA signature was compared with current blood-based markers, and a cost-effectiveness analysis of the miRNA signature against the current practice of endoscopy was performed. All clinical samples used for this study were collected and data analyzed between April 1997 and March 2018. Main Outcomes and Measures: Assessment of diagnostic efficiency on the basis of area under the curve (AUC), specificity, and sensitivity. Results: The data sets for the genome-wide expression profiling analysis stage included 598 total patient samples (284 [55.4%] from men; mean [SE] patient age, 65.7 [0.5] years). The resulting 10-miRNA signature was validated in 2 retrospective GC serum cohorts (586 patients; 348 [59.4%] men, mean [SE] age, 66.0 [0.7] years), which led to the establishment of a 5-miRNA signature (AUC, 0.90; 95% CI, 0.85-0.94) that also exhibited high levels of diagnostic performance in patients with stage I disease (AUC, 0.89; 95% CI, 0.83-0.94). A risk-scoring model was derived and the assay was optimized to a minimal number of miRNAs. The performance of the resulting 3-miRNA signature was then validated in a prospective cohort of patients with GC (349 patients; 124 [70.5%] men, median [range] age, 66.0 [0.66] years). The final 3-miRNA signature (miR-18a, miR-181b, and miR-335) exhibited high diagnostic accuracy in all stages of patients (AUC, 0.86; 95% CI 0.83-0.90), including in patients with stage I disease (AUC, 0.85; 95% CI, 0.79-0.91). Furthermore, this miRNA signature was superior to currently used blood markers and outperformed the endoscopic screening in a cost-effectiveness analysis (incremental cost-effectiveness ratio, CNY ¥16162.5 per quality-adjusted life-year [USD $2304.80 per quality-adjusted life-year]). Conclusions and Relevance: These results suggest the potential clinical significance of the 3-miRNA signature as a noninvasive, cost-effective, and facile assay for the early detection of GC.

Evaluation of common genetic variants in vitamin E-related pathway genes and colorectal cancer susceptibility.

Vitamin E is effective for preventing the risk of cancer. However, few studies have elucidated the mechanism of vitamin E in cancer occurrence. Herein, we aimed to identify the genetic variants in vitamin E-related pathway genes associated with colorectal cancer risk. We applied logistic regression models to assess the association between single-nucleotide polymorphisms (SNPs) in vitamin E-related pathway genes and colorectal cancer risk in the Chinese and European population. The false discovery rate (FDR) method was used to correct multiple comparisons. The mRNA and protein expression analysis were evaluated in public database and in-house RNA-Seq data. SCARB1 rs73227586 was identified significantly increased risk of colorectal cancer in the Chinese population (odd ratio (OR) = 1.46, 95% confidence interval (CI) = 1.22-1.75, P = 2.99 × 10-5). This finding was further validated in the European population (OR = 1.11, 95% CI = 1.02-1.20, P = 1.44 × 10-2). Additionally, the mRNA and protein expression of SCARB1 were markedly up-regulated in colorectal tumor tissues. Moreover, rs73227586 T allele could increase the minimum free energy (MFE) and weaken binding ability to transcription factor ELL2. Our findings indicated that SCARB1 may play a carcinogenic role in colorectal cancer. Genetic variants in vitamin E-related pathway genes may concern to be predictors of colorectal cancer risk.

Variation rs9929218 and risk of the colorectal Cancer and adenomas: A meta-analysis.

BACKGROUNDS: Genome-wide association studies (GWAS) have identified multiple common CRC-related (colorectal cancer) SNPs (single nucleotide polymorphisms) including the Cadherin 1(CDH1) rs9929218 may act by increasing the risk of colorectal cancer, colorectal adenoma, or both. These studies, however, reported inconsistent associations. METHODS: To derive a more accurate approximation of the connection, we carried out a meta-analysis of 12 published pieces of research including 11,590 controls and 8192 cases. We used odds ratios (ORs) and 95% confidence intervals (CIs) to evaluate the associations' strength. RESULTS: Meta-analysis implied considerable association between CRC and rs9929218 (OR = 1.21, 95%CI 1.04-1.42 for GG versus AA; OR = 1.22, 95%CI 1.05-1.42 for GG/AG versus AA). In the subgroup analyses, significantly increased risks were found among Europeans. CONCLUSIONS: In summary, our meta-analysis studies in different populations confirmed that SNP rs9929218 is significantly associated with CRC risk and that this variant may have a greater impact on Europeans.

Circulating tumor cells: A surrogate to predict the effect of treatment and overall survival in gastric adenocarcinoma.

BACKGROUND: Circulating tumor cells and serum tumor markers have been found significant in predicting outcome for several malignancies. However, their role in gastric cancer is not fully clarified. We conducted a retrospective study to explore the prognostic value of circulating tumor cells and their applicability in assessing the treatment efficacy in gastric cancers. METHODS: From September 2015 to December 2018, 116 patients with newly pathologically diagnosed gastric adenocarcinoma were enrolled. At both baseline and two courses after chemotherapy, the data of circulating tumor cells and serum tumor markers, such as CEA, CA72-4, CA19-9, CA50, and CA242, were collected. The relationships between the change trend of circulating tumor cells and the treatment efficacy were analyzed after chemotherapy, with a paired t-test. Univariate and multivariable analysis were used to find prognostic factors for overall survival (OS). RESULTS: We found there is a significant difference between the circulating tumor cells-positive and circulating tumor cells-negative before and after therapy (mOS 12.6 vs. 31.6 months, P<0.001; mOS 12.4 vs. 24.2 months, P=0.002), respectively. Also, differentiation, pre-therapeutic circulating tumor cells and therapeutic response were independent predictors of overall survival. Following two courses of chemotherapy, the number of circulating tumor cells increased obviously in the progressive disease group (P=0.002), while they decreased in the non-progressive disease group (P=0.02). Thus, the change in the circulating tumor cells count had a close association with the therapeutic response (P=0.004). CONCLUSION: Generally, circulating tumor cells provide a novel tool to evaluate the outcomes of gastric cancer patients. Since the change of circulating tumor cells was highly related to treatment response, it may be an auxiliary to assess the effect of chemotherapy, leading an earlier adjustment of following regimens.