Prognostic Biomarker For Colorectal Cancer Research Articles

Serum exosomal miR-122 as a potential diagnostic and prognostic biomarker of colorectal cancer with liver metastasis.

Background: Liver is the most common site for metastatic spread of CRC at the time of diagnosis which leads to high mortality. This study aimed to identify novel circulating exosomal miRNAs as biomarkers of colorectal cancer (CRC) with liver metastasis (LM).Materials and methods: Candidate miRNAs were selected through integrated analysis of Gene Expression Omnibus (GEO) database as well as clinical samples. Exosomes isolated from serum and cultured media were identified by using transmission electron microscopy (TEM) and western blot. The expression levels and diagnostic value of candidate miRNAs were further tested and validated through qRT-PCR and receiver operating characteristic curve (ROC) analysis. The association of candidate miRNA expressions with patients' prognosis was analyzed with logistic regression and Cox proportional hazards regression models.Results: After integrated analysis of three GEO datasets and clinical samples, miR-122 was discovered to be remarkably overexpressed in tissues of CRC patients. Then we revealed that elevated serum miR-122 was tumor-derived by being packaged into exosomes. The expressions of serum exosomal miR-122 were significantly upregulated in CRC patients, especially in those with LM. Serum exosomal miR-122 expressions could differentiate CRC patients with LM from healthy controls and patients without LM with area under the ROC curve (AUC) of 0.89 and 0.81. Uni- and multivariate logistic regression showed that serum exosomal miR-122 was an independent prognostic indicator of CRC patients.Conclusions: Serum exosomal miR-122 was a novel potential diagnostic and prognostic biomarker in CRC patients with LM.

Two precision medicine predictive tools for six malignant solid tumors: from gene-based research to clinical application

BackgroundThe current study aimed to construct competing endogenous RNA (ceRNA) regulation network and develop two precision medicine predictive tools for colorectal cancer (CRC).MethodsDifferentially expressed (DE) analyses were performed between CRC tissues and normal tissues. A ceRNA regulation network was constructed based on DElncRNAs, DEmiRNAs, and DEmRNAs.ResultsFifteen mRNAs (ENDOU, MFN2, FASLG, SHOC2, VEGFA, ZFPM2, HOXC6, KLK10, DDIT4, LPGAT1, BEX4, DENND5B, PHF20L1, HSP90B1, and PSPC1) were identified as prognostic biomarkers for CRC by multivariate Cox regression. Then a Fifteen-mRNA signature was developed to predict overall survival for CRC patients. Concordance indexes were 0.817, 0.838, and 0.825 for 1-, 2- and 3-year overall survival. Patients with high risk scores have worse OS compared with patients with low risk scores.ConclusionThe current study provided deeper understanding of prognosis-related ceRNA regulatory network for CRC. Two precision medicine predictive tools named Smart Cancer Survival Predictive System and Gene Survival Analysis Screen System were constructed for CRC. These two precision medicine predictive tools can provide valuable precious individual mortality risk prediction before surgery and improve the individualized treatment decision-making.

MicroRNA-9-5p-CDX2 Axis: A Useful Prognostic Biomarker for Patients with Stage II/III Colorectal Cancer.

A lack of caudal-type homeobox transcription factor 2 (CDX2) protein expression has been proposed as a prognostic biomarker for colorectal cancer (CRC). However, the relationship between CDX2 levels and the survival of patients with stage II/III CRC along with the relationship between microRNAs (miRs) and CDX2 expression are unclear. Tissue samples were collected from patients with stage II/III CRC surgically treated at Kyoto University Hospital. CDX2 expression was semi-quantitatively evaluated by immunohistochemistry (IHC). The prognostic impacts of CDX2 expression on overall survival (OS) and relapse-free survival (RFS) were evaluated by multivariable statistical analysis. The expression of miRs regulating CDX2 expression and their prognostic impacts were analyzed using The Cancer Genome Atlas Program for CRC (TCGA-CRC). Eleven of 174 CRC tissues lacked CDX2 expression. The five-year OS and RFS rates of patients with CDX2-negative CRC were significantly lower than those of CDX2-positive patients. Multivariate analysis of clinicopathological features revealed that CDX2-negative status is an independent marker of poor prognosis in stage II/III CRC. miR-9-5p was shown to regulate CDX2 expression. TCGA-CRC analysis showed that high miR-9-5p expression was significantly associated with poor patient prognosis in stage II/III CRC. In conclusion, CDX2, the post-transcriptional target of microRNA-9-5p, is a useful prognostic biomarker in patients with stage II/III CRC.

A Five-microRNA Signature as Prognostic Biomarker in Colorectal Cancer by Bioinformatics Analysis.

Mounting evidence has demonstrated that a lot of miRNAs are overexpressed or downregulated in colorectal cancer (CRC) tissues and play a crucial role in tumorigenesis, invasion, and migration. The aim of our study was to screen new biomarkers related to CRC prognosis by bioinformatics analysis. By using the R language edgeR package for the differential analysis and standardization of miRNA expression profiles from The Cancer Genome Atlas (TCGA), 502 differentially expressed miRNAs (343 up-regulated, 159 down-regulated) were screened based on the cut-off criteria of p < 0.05 and |log2FC|>1, then all the patients (421) with differentially expressed miRNAs and complete survival time, status were then randomly divided into train group (212) and the test group (209). Eight miRNAs with p < 0.005 were revealed in univariate cox regression analysis of train group, then stepwise multivariate cox regression was applied for constituting a five-miRNA (hsa-miR-5091, hsa-miR-10b-3p, hsa-miR-9-5p, hsa-miR-187-3p, hsa-miR-32-5p) signature prognostic biomarkers with obviously different overall survival. Test group and entire group shown the same results utilizing the same prescient miRNA signature. The area under curve (AUC) of receiver operating characteristic (ROC) curve for predicting 5 years survival in train group, test group, and whole cohort were 0.79, 0.679, and 0.744, respectively, which demonstrated better predictive power of prognostic model. Furthermore, Univariate cox regression and multivariate cox regression considering other clinical factors displayed that the five-miRNA signature could serve as an independent prognostic factor. In order to predict the potential biological functions of five-miRNA signature, target genes of these five miRNAs were analyzed by Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathway and Gene Ontology (GO) enrichment analysis. The top 10 hub genes (ESR1, ADCY9, MEF2C, NRXN1, ADCY5, FGF2, KITLG, GATA1, GRIA1, KAT2B) of target genes in protein protein interaction (PPI) network were screened by string database and Cytoscape 3.6.1 (plug-in cytoHubba). In addition, 19 of target genes were associated with survival prognosis. Taken together, the current study showed the model of five-miRNA signature could efficiently function as a novel and independent prognosis biomarker and therapeutic target for CRC patients.

MyD88 mediates colorectal cancer cell proliferation, migration and invasion via NF‑κB/AP‑1 signaling pathway.

The role of myeloid differentiation factor 88 (MyD88) in malignant tumors is largely unknown. Therefore, in this study, we aimed to examine the function and underlying mechanism of MyD88 in colorectal carcinoma in vitro using SW480 and HCT116 cell lines and in vivo using a nude mouse model. SW480 and HCT116 cells were infected with a lentiviral-based effective MyD88 siRNA virus. CCK-8 and colony formation assay were used to assess cell proliferation. Transwell and scratch assays were used to test the migration of colorectal cancer cells, and the Transwell assay was further used to analyze the invasiveness of colorectal cancer cells. Western blotting was performed to analyze the underlying mechanism of MyD88 regulation. In vitro experiments demonstrated that silencing MyD88 in SW480 and HCT116 cells markedly suppressed growth and invasion. Furthermore, MyD88 knockdown affected the MyD88-NF-κB/AP-1 signaling pathways in SW480 and HCT116 cells. In vivo, MyD88 knockdown inhibited tumor growth in a HCT116 cell subcutaneous nude model. We found that knockdown of the MyD88 gene can affect proliferation, invasion, and migration of colorectal cancer cells. We further verified that MyD88 knockdown can reduce the activity of NF-κB and AP-1 pathways. These results show that MyD88 gene plays an important role in promoting colorectal cancer, and thus can be exploited as a potential diagnostic and prognostic biomarker for colorectal cancer.

High clusterin (CLU) mRNA expression levels in tumors of colorectal cancer patients predict a poor prognostic outcome

ObjectivesClusterin (CLU) is a multifunctional intra-/extra-cellular molecular chaperone with indications of serving as a promising prognostic biomarker for colorectal cancer (CRC). Several studies have examined the potential prognostic value of the CLU protein in CRC; however, our research follows an alternative approach, focusing on the CLU mRNA expression. Design and methodsTotal RNA from 172 cancerous tissue specimens and 39 paired non-cancerous ones was isolated and 2 μg of this were subjected to reverse transcription with an oligo-dT primer. The single stranded DNA, which was synthesized, was amplified with an in-house developed highly sensitive and precise qPCR method, using specific pair of primers for the CLU molecule. Finally, an extensive biostatistical analysis took place for the assessment of the results. ResultsPatients with tumors expressing high CLU mRNA levels had a higher probability for poor outcome (relapse and death), comparing to those with CLU mRNA-negative tumors. This association between CLU mRNA expression status and both disease-free survival (DFS) and overall survival (OS) is evident in Cox regression analysis and is also depicted in the Kaplan-Meier survival curves. Consistently, the aforementioned associations and the CLU mRNA expression levels are significantly enhanced as CRC tumors progress from TNM stage I to IV, further supporting the functional implication of CLU in tumorigenesis. ConclusionsHigh CLU mRNA levels in CRC tumors can act as a new adverse prognostic biomarker of DFS and OS for CRC, independent of clinicopathological and biological features of the patient.

The role of double-strand break repair, translesion synthesis, and interstrand crosslinks in colorectal cancer progression-clinicopathological data and survival.

DNA repair is a new and important pathway that explains colorectal carcinogenesis. This study will evaluate the prognostic value of molecular modulation of double-strand break repair (XRCC2 and XRCC5); DNA damage tolerance/translesion synthesis (POLH, POLK, and POLQ), and interstrand crosslink repair (DCLRE1A) in sporadic colorectal cancer (CRC). Tumor specimens and matched healthy mucosal tissues from 47 patients with CRC who underwent surgery were assessed for gene expression of XRCC2, XRCC5, POLH, POLK, POLQ, and DCLRE1A; protein expression of Polk, Ku80, p53, Ki67, and mismatch repair MLH1 and MSH2 components; CpG island promoter methylation of XRCC5, POLH, POLK, POLQ, and DCLRE1A was performed. Neoplastic tissues exhibited induction of POLK (P < .001) and DCLRE1A (P < .001) expression and low expression of POLH (P < .001) and POLQ (P < .001) in comparison to healthy paired mucosa. Low expression of POLH was associated with mucinous histology and T1-T2 tumors (P = .038); low tumor expression of POLK was associated with distant metastases (P = .042). CRC harboring POLK promoter methylation exhibited better disease-free survival (DFS) (P = .005). This study demonstrated that low expression or unmethylated POLH and POLK were related to worse biological behavior tumors. However, POLK methylation was associated with better DFS. POLK and POLH are potential prognostic biomarkers in CRC.

Roles of microRNAs as non-invasive biomarker and therapeutic target in colorectal cancer.

MicroRNAs are endogenous, short non-coding RNA molecules that function as critical regulators of various biological processes. There is a strong functional evidence linking the involvement of dysregulated miRNAs to the occurrence, development and progression of colorectal cancer. Studies indicate that while overexpression of oncomiRs, and repression of tumor suppressor miRNAs tends to drive the overall tumorigenic process, the global picture of aberrant miRNA expression in colorectal cancer can classify the disease into multiple molecular phenotypes. Moreover, the expression pattern of miRNAs in colorectal cancer make them viable disease determinants as well as potential therapeutic targets. Through this review, we will summarize the importance of miRNAs in the etiology and progression of colorectal cancer. Specifically, we will explore the key role played by these RNA molecules as likely therapeutic avenues and the strategies presently available to target them. Finally, we will investigate the role of miRNAs as potential non-invasive diagnostic and prognostic biomarkers in colorectal cancer.

557P - Loss of CDX-2 expression is an independent poor prognostic biomarker in colorectal cancer

BackgroundLoss of caudal-type homeobox transcription factor-2 (CDX-2) expression in colorectal cancers (CRC) has recently been proposed as a predictive biomarker for response to chemotherapy and also prognosis. However, the data on relationship between alterations in CDX-2 expression and clinicopathological variables remain limited. We herein aimed to investigate the clinicopathological factors and prognostic implications associated with loss of CDX-2 expression in CRC patients. MethodsImmunohistochemistry for CDX-2 expression was performed on formalin-fixed, paraffin-embedded tissue samples from 427 patients with CRC. Correlation between CDX-2 expression and clinicopathological characteristics were evaluated. Univariate and multivariate survival analyses were performed to reveal the prognostic value of loss of CDX-2 expression. ResultsOf 427 patients, 85% were stage I-III. Seventy six percent had left-sided primary tumors. Deficient mismatch repair (dMMR) was found in 12%. CDX-2-negative expression was identified in 18 out of 427 (4.2%) patients. Loss of CDX-2 expression was more commonly found in patient with right-sided tumors rather than left-sided tumors (9.4% vs 2.8% respectively, p=0.005) and dMMR compared to proficient MMR (11.5% vs 3.3% respectively, p=0.006). There was no association between CDX-2 expression and sex, stage, histologic subtype, tumor differentiation and lymphovascular/perineural invasion. By univariate analysis, patients with CDX-2 loss of expression had significantly worse overall survival (OS) and disease free survival (DFS) than those with CDX-2 positive expression (median OS 1.6 vs 11.6 months (mo), p<0.001; median DFS 1.33mo vs NR, p=0.003). By multivariate analysis, loss of CDX-2 expression remained a negative prognostic factor for OS (hazard ratio 2.32; 95%CI 1.25-4.28, p=0.007). ConclusionsLoss of CDX-2 expression was associated with right-sided tumor and dMMR status. Moreover, loss of CDX-2 expression is a poor prognostic factor for OS, even among patients with dMMR tumors. Legal entity responsible for the studyThe authors. FundingFaculty of Medicine Siriraj Hospital. DisclosureAll authors have declared no conflicts of interest.

Diagnostic and prognostic potential of tissue and circulating long non-coding RNAs in colorectal tumors.

Long non-coding RNAs (lncRNAs) are members of the non-protein coding RNA family longer than 200 nucleotides. They participate in the regulation of gene and protein expression influencing apoptosis, cell proliferation and immune responses, thereby playing a critical role in the development and progression of various cancers, including colorectal cancer (CRC). As CRC is one of the most frequently diagnosed malignancies worldwide with high mortality, its screening and early detection are crucial, so the identification of disease-specific biomarkers is necessary. LncRNAs are promising candidates as they are involved in carcinogenesis, and certain lncRNAs (e.g., CCAT1, CRNDE, CRCAL1-4) show altered expression in adenomas, making them potential early diagnostic markers. In addition to being useful as tissue-specific markers, analysis of circulating lncRNAs (e.g., CCAT1, CCAT2, BLACAT1, CRNDE, NEAT1, UCA1) in peripheral blood offers the possibility to establish minimally invasive, liquid biopsy-based diagnostic tests. This review article aims to describe the origin, structure, and functions of lncRNAs and to discuss their contribution to CRC development. Moreover, our purpose is to summarise lncRNAs showing altered expression levels during tumor formation in both colon tissue and plasma/serum samples and to demonstrate their clinical implications as diagnostic or prognostic biomarkers for CRC.

Oncogenic splicing abnormalities induced by DEAD-Box Helicase 56 amplification in colorectal cancer.

Alternative splicing, regulated by DEAD‐Box Helicase (DDX) families, plays an important role in cancer. However, the relationship between the DDX family and cancer has not been fully elucidated. In the present study, we identified a candidate oncogene DDX56 on Ch.7p by a bioinformatics approach using The Cancer Genome Atlas (TCGA) dataset of colorectal cancer (CRC). DDX56 expression was measured by RT‐qPCR and immunochemical staining in 108 CRC patients. Clinicopathological and survival analyses were carried out using three CRC datasets. Biological roles of DDX56 were explored by gene set enrichment analysis (GSEA), and cell proliferation in vitro and in vivo, cell cycle assays, and using DDX56‐knockdown or overexpressed CRC cells. RNA sequencing was carried out to elucidate the effect of DDX56 on mRNA splicing. We found that DDX56 expression was positively correlated with the amplification of DDX56 and was upregulated in CRC cells. High DDX56 expression was associated with lymphatic invasion and distant metastasis and was an independent poor prognostic factor. In vitro analysis, in vivo analysis and GSEA showed that DDX56 promoted proliferation ability through regulating the cell cycle. DDX56 knockdown reduced intron retention and tumor suppressor WEE1 expression, which functions as a G2‐M DNA damage checkpoint. We have identified DDX56 as a novel oncogene and prognostic biomarker of CRC that promotes alternative splicing of WEE1.

The Efficacy of miR-20a as a Diagnostic and Prognostic Biomarker for Colorectal Cancer: A Systematic Review and Meta-Analysis.

Background: MicroRNAs have altered expression levels in various diseases and may play an important role in the diagnosis and prognosis of colorectal cancer (CRC). Methods: We systemically reviewed and quantitatively synthesized the scientific evidence pertaining to microRNA-20a (miR-20a) as a CRC biomarker. A keyword and reference search in PubMed yielded 32 studies, in which miR-20a was measured in feces, serum, or tumor tissue. Data were extracted from a total of 5014 cancer cases and 2863 controls. Results: Twenty out of 21 relevant studies found that miR-20a was upregulated in CRC patients compared to controls. Meta-analysis revealed a pooled miR-20a fold change of 2.45 (95% CI: 2.24–2.66) in CRC patients versus controls. To estimate sensitivity and specificity of miR-20a as a diagnostic biomarker of CRC, a pooled area under the receiver operating characteristic curve (AUROC) was calculated (0.70, 95% CI: 0.63–0.78). The prognostic capacity of miR-20a was assessed using hazard ratios (HRs) for the overall survival (OS). The meta-analysis estimated the pooled HR for OS to be 2.02 (95% CI: 0.90–3.14) in CRC patients with high miR-20a expression. Conclusions: miR-20a may be a valid biomarker for CRC detection but may not be a strong predictor of poor prognosis in CRC.

The emerging role of noncoding RNAs in colorectal cancer chemoresistance.

Colorectal cancer (CRC) is the third most prevalent cancer in the world and one of the most lethal human malignancies. Chemotherapy with 5-fluorouracil, platinum, hydroxycamptothecin, vincristine, methotrexate, irinotecan, paclitaxel and/or cetuximab has significantly improved the survival of CRC patients. However, most CRC patients eventually develop chemoresistance, resulting in a poor prognosis. The mechanisms involved in CRC chemoresistance are complex and, as yet, inconclusive. Noncoding RNAs (ncRNAs), such as small nucleolar RNAs (snoRNAs), microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), represent transcripts without protein-coding potential. Accumulating evidence indicates that multiple deregulated ncRNAs, including miRNAs and lncRNAs, play pivotal roles in the development of chemoresistance in CRC. This notion has potential clinical implications. In this review, we highlight the emerging roles and the regulatory mechanisms by which miRNAs and lncRNAs affect CRC chemoresistance. Tumor-specific miRNAs and lncRNAs may serve as novel therapeutic targets and prognostic biomarkers for CRC.

Neurexophilin and PC-esterase domain family member 4 (NXPE4) and prostate androgen-regulated mucin-like protein 1 (PARM1) as prognostic biomarkers for colorectal cancer.

Owing to the high morbidity and mortality, novel biomarkers in the occurrence and development of colorectal cancer (CRC) are needed nowadays. In this study, the CRC-related datasets were downloaded from the Gene Expression Omnibus (GEO) database and The Cancer Genome Atlas (TCGA) database. After screening the differentially expressed genes (DEGs) in R software, a total of 238 upregulated and 199 downregulated DEGs were revealed simultaneously. Then the Kaplan-Meier survival analysis and Cox regression analysis were used to reveal the prognostic function of these DEGs. Neurexophilin and PC-esterase domain family member 4 (NXPE4) and prostate androgen-regulated mucin-like protein 1 (PARM1) were two outstanding independent overall survival (OS) and relapse-free survival (RFS) prognostic genes of CRC in TCGA database. We next verified the expression of NXPE4 and PARM1 messenger RNA (mRNA) levels were significantly lower in CRC tumor tissue than in the adjacent noncancerous tissue in our clinical samples, and NXPE4 mRNA expression level was related to the tumor location and tumor size, while PARM1 was related to tumor location, lymph nodes metastasis, and tumor size. This study demonstrated that NXPE4 and PARM1 might be two potential novel prognostic biomarkers for CRC.

Abstract 5238: Clinical significance of GET4 expression in colorectal cancer

Abstract Background: Colorectal cancer (CRC) is one of the most common cancers worldwide and the second leading cause of cancer-related deaths in developed countries, with the majority of deaths being attributed to distant metastasis. Therefore, it is necessary to identify a novel biomarker for cancer progression and metastasis, one that could also be a useful therapeutic target in CRC. Amplification of chromosome 7p is frequent in CRC, and it has been considered to harbor driver genes that promote tumorigenesis or tumor progression by the gain of function. We aimed to identify novel candidate driver genes on chromosome 7p and to clarify the clinical significance of their expression in CRC. Material and Methods: 1. We selected the candidate genes that satisfied the following criteria using CRC data from The Cancer Genome Atlas (TCGA). 1) The DNA copy number and mRNA expression are positively correlated with each other, 2) overexpressed in the tumor tissues compared to the normal tissues. 2. The mRNA expression of the candidate genes was measured in 147 surgically-resected CRC tissues and the paired normal tissues in our hospital by quantitative RT-PCR. The differences of mRNA expression between CRC tissues and normal tissues were analyzed by Mann Whitney U-test. 3. Survival analysis between high and low expression group of the candidate genes was performed by the Kaplan-Meier method. Correlation between the mRNA expression of the candidate genes and the clinicopathological factors were analyzed by Fisher’s exact test. 4. Gene Set Enrichment Analysis (GSEA) was performed in CRC data from TCGA to clarify the correlation between the candidate genes and gene sets that are associated with tumorigenesis or tumor progression. Results: The Golgi to ER traffic protein 4 (GET4) was identified as a candidate driver gene. GET4 is known to be one factor of the BCL2-associated athanogene 6 (BAG6) chaperone complex and function as a regulator for the nucleo-cytoplasmic transport of BAG6. The BAG6 complex is implicated in diverse cellular processes including apoptosis, co-chaperone, and DNA damage response. The expression of GET4 was significantly higher in CRC tissues than in normal colon tissues (p=0.03), and it correlated with depth invasion (p=0.02), and lymphatic invasion (p=0.01). The high GET4 expression group had a significantly poorer prognosis than the low expression group (p=0.02). On multivariate analysis, distant metastasis was an independent prognostic factor affecting OS (p&amp;lt;0.05) with hazard ratios (95% CI) of 66.6 (5.46-1649.3) among clinicopathological factors. GSEA showed that GET4 expression was negatively correlated with the pathway associated with the Rb-related protein p130, which belongs to the RB gene family proved to be a tumor suppressor. Conclusions: GET4 could be a promising driver gene of CRC on chromosome 7p possibly through regulating the location of BAG6. GET4 may be a therapeutic target as well as a poor prognostic biomarker in CRC. Note: This abstract was not presented at the meeting. Citation Format: Kensuke Koike, Takaaki Masuda, Kuniaki Sato, Yuushi Motomura, Jyunnichi Takahashi, Dai Shimizu, Shotaro Kuramitsu, Atsushi Fujii, Akihiro Kitagawa, Miwa Noda, Yusuke tsuruda, Hajime Ootu, Yousuke Kuroda, Hidetoshi Eguchi, Takashi Nakagawa, Koushi Mimori. Clinical significance of GET4 expression in colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 5238.

Clinical Potential of Circulating Tumor Cells in Colorectal Cancer: A Prospective Study

OBJECTIVES:Circulating tumor cells (CTCs) in the blood have been used as diagnostic markers in patients with colorectal cancer (CRC). In this study, we evaluated a CTC detection system based on cell size to assess CTCs and their potential as early diagnostic and prognostic biomarkers for CRC.METHODS:From 2014 to 2015, 88 patients with newly diagnosed CRC, who were scheduled for surgery, and 31 healthy volunteers were enrolled and followed up in Pusan National University Hospital. CTCs were enriched using a centrifugal microfluidic system with a new fluid-assisted separation technique (FAST) and detected by cytomorphological evaluation using fluorescence microscopy.RESULTS:Two or more CTCs were detected using FAST in 74 patients and 3 healthy volunteers. The number of CTCs in the CRC group was significantly higher than that in the healthy volunteers (P < 0.001). When a receiver operating characteristic curve was created to differentiate patients with CRC from healthy volunteers, the sensitivity and specificity were almost optimized when the critical CTC value was 5/7.5 mL of blood. When this value was used, the sensitivity and specificity in differentiating patients with CRC from the healthy controls were 75% and 100%, respectively. In patients with CRC with ≥5 CTCs, vascular invasion was frequently identified (P = 0.035). All patients with stage IV were positive for CTCs. Patients with ≥5 CTCs showed a trend toward poor overall and progression-free survival.DISCUSSION:Our study demonstrated promising results with the use of FAST-based CTC detection for the early diagnosis and prognosis of CRC.

Screening key genes and signaling pathways in colorectal cancer by integrated bioinformatics analysis

The aim of the present study was to identify potential key genes associated with the progression and prognosis of colorectal cancer (CRC). Differentially expressed genes (DEGs) between CRC and normal samples were screened by integrated analysis of gene expression profile datasets, including the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was conducted to identify the biological role of DEGs. In addition, a protein-protein interaction network and survival analysis were used to identify the key genes. The profiles of GSE9348, GSE22598 and GSE113513 were downloaded from the GEO database. A total of 405 common DEGs were identified, including 236 down- and 169 upregulated. GO analysis revealed that the downregulated DEGs were mainly enriched in ‘detoxification of copper ion’ [biological process, (BP)], ‘oxidoreductase activity, acting on CH-OH group of donors, NAD or NADP as acceptor’ [molecular function, (MF)] and ‘brush border’ [cellular component, (CC)]. Upregulated DEGs were mainly involved in ‘nuclear division’ (BP), ‘snoRNA binding’ (MF) and ‘nucleolar part’ (CC). KEGG pathway analysis revealed that DEGs were mainly involved in ‘mineral absorption’, ‘nitrogen metabolism’, ‘cell cycle’ and ‘caffeine metabolism’. A PPI network was constructed with 268 nodes and 1,027 edges. The top one module was selected, and it was revealed that module-related genes were mainly enriched in the GO terms ‘sister chromatid segregation’ (BP), ‘chemokine activity’ (MF), and ‘condensed chromosome (CC)’. The KEGG pathway was mainly enriched in ‘cell cycle’, ‘progesterone-mediated oocyte maturation’, ‘chemokine signaling pathway’, ‘IL-17 signaling pathway’, ‘legionellosis’, and ‘rheumatoid arthritis’. DNA topoisomerase II-α (TOP2A), mitotic arrest deficient 2 like 1 (MAD2L1), cyclin B1 (CCNB1), checkpoint kinase 1 (CHEK1), cell division cycle 6 (CDC6) and ubiquitin conjugating enzyme E2 C (UBE2C) were indicated as hub genes. Furthermore, survival analysis revealed that TOP2A, MAD2L1, CDC6 and CHEK1 may serve as prognostic biomarkers in CRC. The present study provided insights into the molecular mechanism of CRC that may be useful in further investigations.

Circulating Noncoding RNAs Have a Promising Future Acting as Novel Biomarkers for Colorectal Cancer.

Colorectal cancer (CRC) is one of the most common malignant tumors worldwide, causing a large number of cancer-related deaths each year. Patients are usually diagnosed at advanced and incurable stages due to the lack of suitable screening methods for early detection. Noncoding RNAs (ncRNAs), including small and long noncoding RNAs (lncRNA), are known to have significant regulatory functions, and accumulating evidence suggests that circulating ncRNAs have potential applications as noninvasive biomarkers for diagnosing CRC, evaluating its prognosis, or predicting chemosensitivity in the general population. In this review, we summarize the origins of circulating ncRNAs and provide details of single and multiple circulating ncRNAs that might have roles as diagnostic and prognostic biomarkers in CRC. We end by discussing circulating ncRNAs that may distinguish patients with resistance to chemotherapy.

Identification and development of long non-coding RNA-associated regulatory network in colorectal cancer.

Colorectal cancer (CRC) is one of the leading causes of cancer‐associated death globally. Long non‐coding RNAs (lncRNAs) have been identified as micro RNA (miRNA) sponges in a competing endogenous RNA (ceRNA) network and are involved in the regulation of mRNA expression. This study aims to construct a lncRNA‐associated ceRNA network and investigate the prognostic biomarkers in CRC. A total of 38 differentially expressed (DE) lncRNAs, 23 DEmiRNAs and 27 DEmRNAs were identified by analysing the expression profiles of CRC obtained from The Cancer Genome Atlas (TCGA). These RNAs were chosen to develop a ceRNA regulatory network of CRC, which comprised 125 edges. Survival analysis showed that four lncRNAs, six miRNAs and five mRNAs were significantly associated with overall survival. A potential regulatory axis of ADAMTS9‐AS2/miR‐32/PHLPP2 was identified from the network. Experimental validation was performed using clinical samples by quantitative real‐time PCR (qRT‐PCR), which showed that expression of the genes in the axis was associated with clinicopathological features and the correlation among them perfectly conformed to the ‘ceRNA theory’. Overexpression of ADAMTS9‐AS2 in colon cancer cell lines significantly inhibited the miR‐32 expression and promoted PHLPP2 expression, while ADAMTS9‐AS2 knockdown had the opposite effects. The constructed novel ceRNA network may provide a comprehensive understanding of the mechanisms of CRC carcinogenesis. The ADAMTS9‐AS2/miR‐32/PHLPP2 regulatory axis may serve as a potential therapeutic target for CRC.

The study of the significance and prognosis of the differential expressed miRNAs and their target genes associated with biological in colorectal cancer.

e15088 Background: MicroRNAs (miRNAs) have been related to prognostic indicators (such as stage and survival) in colorectal cancer. This study aimed to identify differentially expressed miRNAs and their target genes associated with biological significance and prognosis in colorectal cancer. Methods: The colorectal cancer, colorectal adenoma, and normal samples were obtained from the gene expression profile of GSE71187. A union of differentially expressed genes (DEGs) in the three groups was identified. The significantly different modules with highly interconnected DEGs were identified using weighted correlation network analysis (WGCNA) and were enriched to the KEGG pathway and GO function. Subsequently, the protein-protein interaction (PPI) network for DEGs in the module and the integrated regulatory network of miRNA-DEGs were constructed. In addition, the relationship of target DEGs and prognostic information was analyzed. Results: Three significantly different modules were identified, such as the brown, turquoise, and grey modules. The turquoise module including LTC4S, KLRK1, UNC5C, etc., which was mainly enriched to cell adhesion, cytokine−cytokine receptor interaction, and chemokine signaling pathway, inhibited the development of colorectal cancer. Subsequently, PPI network was constructed with the 678 DEGs in the three modules. Moreover, the miRNA-DEGs network was constructed with the 17 target DEGs (CXCR1, LTC4S, BTK, IGF1, etc.) and 14 miRNA (hsa-miR-335-5p, etc.). Finally, the overexpressed LTC4S was a good prognostic biomarker for colorectal cancer. Conclusions: The hsa-miR-335-5p might have potential prognosis value by targeting LTC4S and CXCR1 in colorectal cancer.