Clinicopathological Features Of Colorectal Cancer Research Articles

Expression levels of miR-143-3p and -424-5p in colorectal cancer and their clinical significance.

Colorectal cancer (CRC) is one of the most prevalent cancers and microRNAs are involved in colorectal carcinogenesis and progression. The role of our candidate microRNAs (miR-143-3p, -424-5p, -212-3p and -34a-3p) have been investigated in various cancers. The aim of the current study was to evaluate expression levels of microRNAs (miR-143-3p, -424-5p, -212-3p and -34a-3p) in the sera of patients with CRC in order to identify potential non-invasive biomarker for CRC and investigate the relationship between their expression and clinicopathological features of CRC. The serological expression of candidate microRNAs were measured in 124 participants, including 62 CRC patients and 62 healthy controls and the serum expression levels of candidate miRNAs were quantified by stemloop reverse transcriptionquantitative polymerase chain reaction. In the present study, results showed a significant upregulation expression level of miR-424-5p (P< 0.001) and decreased expression level of miR143-3p was observed in the sera of patients with CRC (P< 0.001). Receiver operating characteristic (ROC) curve analysis demonstrated the area of miR-424-5p and miR-143-3p under the ROC curve for CRC diagnosis were 0.703 and 0.724 respectively (P< 0.001). In addition, down expression of miR-143-3p was significantly associated with tumor size (P= 0.005) and lymph node metastasis (P= 0.020) in CRC patients. The present investigation suggested that low expression of miR-143-3p and increasing level of miR-424-5p in CRC patients may play an important role in development of CRC and they could function as potential non-invasive biomarkers for CRC.

Overexpression of Arginase-1 is an indicator of poor prognosis in patients with colorectal cancer

AimArginase-1 (Arg-1) metabolizes l-arginine to l-ornithine and urea. It has been documented to have a role in various malignancies. However, the relationship between Arg-1 expression and clinicopathological characteristics of colorectal cancer (CRC) patients remains to be elucidated. The present study aimed to analyze the expression and prognostic value of Arg-1 in patients with CRC. Material and methodsThe mRNA and protein expressions of Arg-1 in fresh colorectal cancer tissue specimens and the corresponding noncancerous tissue specimens were examined by RT-qPCR (n = 24) and western blot analysis (n = 17). Arg-1 expression levels were determined in paraffin-embedded CRC tissue specimens (n = 236) by immunohistochemistry. The associations of Arg-1 expression and clinicopathological features and clinical prognosis in 236 CRC patients were analyzed. ResultsThe expression levels of Arg-1 were significantly higher in the CRC tissues compared with the matched noncancerous tissues, and elevated Arg-1 expression was remarkably associated with stage III-IV tumors (P = 0.007), lymph node metastasis (P = 0.019) and a plasma albumin concentration <35 g/l (P = 0.022). Kaplan-Meier analysis indicated that Arg-1 overexpression was associated with adverse prognoses for overall survival (OS) (P < 0.001) and disease-free survival (DFS) (P < 0.001) in all cases. Further analysis revealed that the patients with high Arg-1 expression had significantly shorter OS and DFS at the advanced stages (III + IV) (P = 0.032 for OS, and P = 0.012 for DFS) but not at the early stages (I + II) (P = 0.194 for OS, and P = 0.065 for DFS). Multivariate analysis revealed that Arg-1 overexpression was an independent prognostic factor for OS (P = 0.002) and DFS (P < 0.001) in patients with CRC. ConclusionThe data indicated that Arg-1 overexpression in CRC may be a marker that can discriminate subgroups of patients with a poor prognosis.

Identification of key genes and pathways involved in microsatellite instability in colorectal cancer.

Microsatellite instability (MSI) has emerged as one of the key biological features of colorectal cancer (CRC). However, controversies remain regarding the association between the MSI status and clinicopathological characteristics of CRC. Therefore, it is crucial to identify potential key genes and pathways associated with MSI in CRC. In the present study, the GSE25071 gene expression profile was retrieved, with thirty-eight cases of microsatellite stable (MSS), five of MSI-High (MSI-H) and three of MSI-Low (MSI-L) CRC patients. The differentially expressed genes (DEGs) were analyzed by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes pathway enrichment, gene set enrichment analysis (GSEA) and gene co-expression network analysis. Weighted gene correlation network analysis (WGCNA) was used for the gene modules and correlation of clinical traits. A total of forty-nine DEGs were identified between MSI-H and MSS, including six upregulated and forty-three downregulated DEGs. Only the DEGs of MSI-H and MSS were subjected to subsequent analysis (limited number of DEGs of MSI-L and MSS, MSI-H and MSI-L). RNA metabolic process, endoplasmic reticulum and chemokine receptor binding were the top ranked terms in GO enrichment. The hub genes of co-expression network of DEGs included zinc finger protein (ZNF) 813, ZNF426, ZNF611, ZNF320 and ZNF573. The GSEA of MSI-H and MSS indicated that the mammalian target of rapamycin complex 1 signaling was significantly enriched with a nominal P-value of 0.038 and normalized enrichment score of 0.446. The WGCNA results showed that the pink module was the top in correlation with MSI status (R2=0.5, P=0.0004). The genes in the pink module were significantly enriched in proteins targeting to endoplasmic reticulum, cytosolic part, structural constituent of ribosome and ribosome pathway. The hub genes identified in the pink module were ribosomal protein L12 (RPL12), RPS3A, RPS9, RPL27A, RPL7, RPL28, RPL14, RPS17, mitochondrial ribosomal protein L16, and G elongation factor, mitochondrial 2. The present study identified key genes and pathways associated with MSI, providing insightful mechanisms.

Association between CA repeat polymorphism in IGF1 gene promoter and colorectal cancer risk in a native Chinese population.

Insulin-like growth factor 1 (IGF1) is implicated in normal cell growth. It has been reported that IGF1 has a mitogenic and anti-apoptotic effect on colorectal cancer cells. However, results of studies on the association between cytosine-adenine (CA) repeat polymorphism in IGF1 gene promoter and colorectal cancer (CRC) risk are inconsistent. We aimed to evaluate the association between CA repeat polymorphism and CRC risk, as well as the relationship with the clinicopathological characteristics of CRC and circulating IGF1 level in a native Chinese population. There were 734 participants who were native Chinese in this case-control study, including 367 CRC cases and 367 age- and sex-matched controls. CA repeat polymorphism was genotyped by PCR and fragment analysis. Odds ratios (ORs) and 95% confidence intervals (CIs) were evaluated by unconditional logistic regression analysis. Circulating level of IGF1 in cases was significantly higher than that in controls (P = 0.002), particularly in males. Less than 38 CA repeats were associated with decreased CRC risk after adjusting for age and sex (37 versus 38 CA repeats: OR = 0.45; 95%CI = 0.26-0.78), especially in males. (CA)18/19 genotype showed approximately half reduced CRC risk comparing to (CA)19/19 genotype (OR = 0.46; 95%CI = 0.25-0.85). There was a significant association between the sum of CA repeats and degree of differentiation of CRC (P = 0.044). We observed a trend that circulating level of IGF1 in individuals with CA ≤ 38 repeats was lower than that in individuals with CA > 38 repeats with a borderline statistically significance in overall and males. In conclusion, our findings support the possible role of CA repeat polymorphism in CRC risk.

Circulating Lymphocytes, PD-L1 Expression on Tumor-infiltrating Lymphocytes, and Survival of Colorectal Cancer Patients with Different Mismatch Repair Gene Status.

Clinical outcomes of checkpoint blockade immunotherapy on colorectal cancer (CRC) are influenced by mismatch repair (MMR) gene status, which is associated with distinct tumor immune infiltrates and systemic inflammatory response status. However, the prognostic value of PD-L1 expression and the systemic inflammatory response for patients with MMR deficiency has not been fully investigated. In this study, we examined the association of systemic inflammatory markers, PD-1/PD-L1 pathway expression, microsatellite instability (MSI) status, and clinicopathological characteristics of CRC with patient survival between MMR-deficient (dMMR) group (N=168) and MMR-proficient (pMMR) group (N=169). We found a large proportion of dMMR CRC patients displayed increased level of systemic inflammatory markers such as C-reactive protein, Neutrophil/Lymphocyte Ratio (NLR), Glasgow Prognostic Score (GPS), and low expression of PD-L1 in tumor stroma. Several systemic inflammatory markers were associated with AJCC stage only in dMMR patients. Similarly, Tumor infiltrating lymphocyte (TIL) PD-L1 or stroma PD-L1 expression was associated with AJCC stage only in dMMR patients. Circulating serum lymphocytes and TIL PD-L1 expression are both independent prognosis predictors for CRC patients. Overall, we found that dMMR CRC displayed a comprehensively distinct tumor immune microenvironment and systemic inflammatory response makers. PD-L1 expression at different location has different impacts on CRC patient survival, and the TIL PD-L1 expression might be a potential predictor for dMMR CRC patient response to anti-PD-1 therapy.

Highly sensitive diagnostic method for colorectal cancer using the ratio of free DNA fragments in serum.

The correlations of the ratio of long-/short-chain DNA fragments in blood with the existence of cancer and the clinicopathological features of colorectal cancer (CRC) were examined. The potential use of this ratio for diagnostic screening was evaluated. DNA concentrations were amplified using Alu247 for long-chain DNA fragments and Alu115 for long- and short-chain DNA fragments. The Alu247/115 ratio was calculated for 60 patients with CRC and 24 healthy volunteers. The correlation of the Alu247/115 ratio with clinicopathological variables and the efficacy of this ratio as a tumor marker were examined. The Alu247/115 ratio cut-off value was set using a receiver operating characteristic (ROC) curve. The Alu247/115 ratio was significantly higher in patients with CRC than in healthy volunteers (P<0.001). The Alu247/115 ratio was also significantly higher in patients with Dukes stage A or B CRC than in healthy volunteers (P=0.034) as well as in patients with Dukes C or D CRC than in those with Dukes A or B CRC (P=0.016). Among patients with CRC, the Alu247/115 ratio was significantly higher in those with than without venous invasion (P=0.031). Using the cut-off value set from the ROC curve, the sensitivity of the Alu247/115 ratio was significantly higher than that of the carcinoembryonic antigen level (P=0.004) or the carbohydrate antigen 19-9 level (P<0.001). Our data suggest that the Alu247/115 ratio is a promising tool for highly sensitive and early detection of CRC.

Overexpression of long noncoding RNA NORAD in colorectal cancer associates with tumor progression.

PurposeThe aim of this study was to elucidate the role and clinical significance of long noncoding RNA-activated by DNA damage (NORAD) in colorectal cancer (CRC).MethodsSixty pairs of tumorous and adjacent nontumorous tissues derived from CRC patients were subjected to quantitative real-time polymerase chain reaction to determine the expression level of NORAD. The serum levels of NORAD expression were also measured in an independent cohort of CRC patients as well as patients with benign diseases and healthy controls. Comparative analyses were performed to investigate the relationships between NORAD levels in tissues and clinicopathological features of CRC. Receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic value of NORAD in patients with CRC. Furthermore, the potential functions of NORAD in the development of CRC were explored in vitro, using the HCT116 and SW1116 CRC cell lines.ResultNORAD expression was significantly upregulated in the tumorous tissues of CRC patients (P<0.001) compared to the adjacent nontumorous tissues. Higher NORAD expression was associated with advanced CRC. Moreover, serum levels supported that NORAD could distinguish CRC patients from healthy controls and patients with benign diseases, indicating a potential diagnostic role in CRC. The ROC curve analysis showed a diagnostic efficacy with area under the curve of 0.800 (95% CI: 0.737–0.853). Mechanistic investigations indicated that NORAD silencing reduced CRC cell proliferation, migration, and invasion.ConclusionNORAD may serve as a novel predictor in CRC and may be a potential target for future therapy.

MicroRNA-488 inhibits progression of colorectal cancer via inhibition of the mitogen-activated protein kinase pathway by targeting claudin-2.

Colorectal cancer (CRC) affects people globally, and lymph node metastasis (LNM) is an important indicator of poor clinical outcome in CRC. The current study aims to evaluate the role of microRNA-448 (miR-488) and claudin-2 (CLDN2) in epithelial-mesenchymal transition (EMT) and LNM of CRC through the MAPK signaling pathway. First, microarray analysis indicated that miR-488 was poorly expressed in CRC, whereas CLDN2 was highly expressed. Additionally, the bioinformatics website MicroRNA.org and the dual luciferase reporter gene assay found that CLDN2 was a target gene of miR-488. Next, the results for the correlations between expression of miR-488 and clinicopathological characteristics of CRC indicated that the expression of miR-488 was closely associated with differentiation degree, LNM, and Dukes stages in CRC patients. Moreover, overexpression of miR-488 inhibited the activation of the MAPK signal transduction pathway. Notably, loss- and gain-of-function experiments demonstrated that upregulation of miR-488 suppressed SW480 cell viability, invasion, and migration and promoted apoptosis in SW480 cells. Finally, overexpression of miR-488 inhibited LNM, microlymphatic vessel density, and tumor growth in nude mice. We conclude that overexpression of miR-488 could suppress the cell proliferation, EMT, and LNM of CRC cells via inhibition of the CLDN2-mediated MAPK signaling pathway, which could be a new molecular therapy target for CRC.

Evaluation of platelet indices as diagnostic biomarkers for colorectal cancer

Altered platelet indices, including platelet count (PC), mean platelet volume (MPV), platelet distribution width (PDW), and plateletcrit (PCT), have been found in various cancer types. This study aimed to evaluate the role of platelet indices as potential biomarkers for the diagnosis of colorectal cancer (CRC), and to assess the association between platelet indices and CRC clinicopathological characteristics. The study included 783 subjects with CRC, 463 subjects with colorectal adenomas (CA), and 689 control subjects from June 2015 to October 2017. All participants’ clinicopathological characteristics were collected and analyzed. Here, we found that PC, MPV and PCT levels in CRC patients were significantly higher than those in CA patients and healthy participants (p < 0.001); however, PDW level in CRC patients was significantly higher than that in healthy participants while lower than that in CA patients. Receiver-operating characteristic (ROC) analysis indicated that combined detection of PCT and CEA appears to be a more effective marker to distinguish CRC patients from CA patients, with 70% sensitivity and 83% specificity. Among CRC patients, PC and PCT levels were associated with TNM stages and tumor size; MPV and PCT levels were associated with vascular invasion. Our findings suggest that altered PC, MPV and PCT levels might serve as potential biomarkers for the diagnosis and prognosis of CRC.

Association study between a genetic polymorphism in cytochrome P450 19 gene rs10046 and colon and rectal cancer

Objective To investigate the relationship between the polymorphism of cytochrome P450 19 (CYP19) gene rs10046 and the risk of colon and rectal cancer. Methods Using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP)to analyze gene polymorphism in CYP 19 gene rs10046 in 198 cases of colon and rectal cancer patients (case group)and 309 cases of healthy controls (control group). The genotype frequency and relative risk of CYP19 gene rs10046 between the two groups were compared and the relationship with the clinicopathological features of colorectal cancer was analyzed. Results In case group, the prevalence rates of CYP19 rs10046 genotypes C/C, C/T and T/T were 28.3%, 44.4% and 27.3%, respectively, and 17.2%, 51.8% and 31.1% in the control group, respectively, with statistical significant difference (P<0.05). Compared with wild-type C/C, the susceptibility of colorectal cancer with the genotypes of C/T and T/T was decreased by 0.521 (95% CI: 0.330-0.822) and 0.532 (95% CI: 0.322-0.880) respectively. Moveover, in the non-smoking group, the risk of colorectal cancer with genotype T/T or C/T was decreased by 0.409 (95% CI: 0.210-0.798) compared with genotype C/C. The interaction was not exist in smoking group. Conclusions The polymorphism of CYP19 gene rs10046 is related to the susceptibility of colon and rectal cancer. The T/T, C/T genotype of CYP19 rs10046 decrease the risk of colon and rectal cancer, and which might be the protective factor of colon and rectal cancer. Key words: Polymorphism, genetic; Cytochrome P-450 enzyme system/GE; Colorectal neoplasms/GE

The roles and mechanism of chemokine receptor type 5 in colorectal cancer proliferation

Objective To examine the expression of chemokine receptor type 5 (CXCR5) in colorectal cancer (CRC) and to explore its relationship with clinicopathological features and cell proliferation in CRC. Methods Immunohistochemical staining method was used to detect the protein expression of CXCR5 in 132 paired specimens of CRC, adjacent and 62 samples of adenoma. Analysing the relationship between CXCR5 with clinicopathological features in CRC. RNA interference (RNAi) technique was applied to construct four CXCR5 short hairpin RNA (shRNA) expression vectors. Lipofectamine 2000 was used to transfer plasmids into colon cancer cell lines LoVo and HCT116. Real-time PCR and Western blotting were used to observe the inhibitory effect of RNAi on CXCR5 expression. Lentivirus production and transduction were used to construct CXCR5 shRNA stably expressed CRC cell lines. CXCR5 overexpressed plasmid was used to construct CXCR5 stably expressed CRC cell lines. cell counting kit-8 (CCK-8) assay and colony formation assay were used to detect the influence of specific CXCR5 on CRC cell. Tumor formation in nude mouse was performed to detect the effects of CXCR5 on the proliferation ability of CRC cells in vivo. FCM were used to detect the cell cycle. Results CXCR5 protein was expressed in 46.97% (62/132) of CRC tissues and 24.19% (15/62) of adenoma tissues, respectively. The protein expression of CXCR5 was negative in adjacent tissues. The protein expression level of CXCR5 in CRC tissues was significantly higher than ademona tissues (P=0.020). The expression of CXCR5 was correlated with relapse, TNM stage, lymph node metastasis and distant metastasis (P=0.004, 0.025, 0.002, 0.008). CCK-8 and colony formation results showed that the CXCR5 shRNA inhibited the proliferation of CRC significantly, whereas overexpression of CXCR5 promoted CRC proliferation in vitro. Tumor formation results in nude mouse showed that CXCR5 silencing inhibited the proliferation and metastasis ability of CRC cells, whereas overexpression of CXCR5 promoted proliferation of CRC cells in vivo. CXCR5 may influence CRC cells proliferation through cell cycle in vitro. Conclusion CXCR5 may play a crucial role in carcinogenesis, development of CRC. CXCR5 could promote proliferation of colon cancer cell both in vitro and in vivo, and may influence CRC development through cell cycle. Key words: Colorectal cancer; Chemokine receptor type 5; Proliferation

Prognostic Value of MUC2 Expression in Colorectal Cancer: A Systematic Review and Meta-Analysis.

Background The reliability of MUC2 as a prognostic marker in colorectal cancer (CRC) is controversial. This study evaluated the association between MUC2 expression levels in CRC tissues and prognosis. Methods The PubMed, Web of Science, Embase, Cochrane Library, China Biology Medicine disc (CBMdisc), Wanfang Database, and China National Knowledge Infrastructure (CNKI) databases were searched to identify studies exploring the relationship between MUC2 expression in CRC tissues and overall survival (OS). Pooled hazard ratios (HRs) and risk ratios (RRs) with 95% confidence intervals (CIs) were used to evaluate the associations between MUC2 expression levels and prognosis and MUC2 expression levels and CRC clinicopathological characteristics, respectively. Results The meta-analysis included 11 studies (2619 patients). Low MUC2 expression level was significantly associated with poor OS (HR, 1.67; 95% CI, 1.43–1.94; P < 0.00001) and disease-free survival (DFS)/recurrence-free survival (RFS) (HR, 1.60; 95% CI, 1.21–2.12; P = 0.001) in patients with CRC. Low MUC2 expression level was associated with advanced TNM stage (RR, 1.42; 95% CI, 1.26–1.60; P < 0.00001), lymph node metastasis (RR, 1.41; 95% CI, 1.25–1.60; P < 0.00001), lymphatic invasion (RR,1.64; 95% CI, 1.26–2.12; P = 0.0002), rectal tumor site (RR, 1.26; 95% CI, 1.09–1.46; P = 0.001), and large tumor size (RR,1.32; 95% CI, 1.02–1.70; P = 0.03). There were no associations between low MUC2 expression level and gender, histological grade, depth of invasion, and distant metastasis. Conclusion The low levels of MUC2 in CRC tissues are poor prognostic factor independent of stage or other well-recognized markers of later-stage disease. Large well-designed cohort studies are required to validate MUC2 as a biomarker for poor prognosis in CRC.

Nrf2/P–glycoprotein axis is associated with clinicopathological characteristics in colorectal cancer

Colorectal cancer (CRC) is the fourth leading cause of cancer−related death worldwide. Activation of ABCB1 gene and its main product, P−glycoprotein, is the common reason for chemoresistance. The nuclear factor–erythroid 2–related factor2 (Nrf2) is directly regulated by Kelch like ECH–associated protein1 (Keap1). In addition, Nrf2 is a key transcriptional factor that regulates efflux transporters, including P−gp. The aim of this study was to investigate the expression levels of Nrf2, Keap1 and ABCB1 in the biopsy samples and their association with clinicopathological features in CRC patients. Both mRNA and protein expression levels were measured by Real−time PCR and immunohistochemistry (IHC), respectively, in biopsies from colonoscopy in 65 CRC patients compared to those in 65 non−CRC individuals. While expression levels of Nrf2 and ABCB1 (P−gp) were markedly higher in both mRNA and protein levels in CRC biopsies (p < 0.01), Keap1 expression level was significantly lower in these samples (p < 0.05). Positive correlations between Nrf2 expression level and tumor size (p = 0.003), lymph node (p = 0.038), distant metastasis (p = 0.008), and smoking status (p = 0.02) were observed. However, P–gp expression was associated only with patient age and smoking status. In addition, there was a positive correlation between protein levels of Nrf2 and P−gp, in both CRC (r = 0.617, p < 0.001) and non−CRC tissues (r = 0.930, p < 0.001). In conclusion, over-expression of Nrf2 and ABCB1/P−gp, as well as down-regulation of mRNA expression level of Keap1 in CRC patients denotes the role of Keap1/Nrf2/ABCB1 axis in CRC progression and chemoresistance. Our data suggest that therapeutic inhibition of Nrf2/ABCB1 signaling can be considered as a novel strategy to improve the efficacy of chemotherapeutics against CRC.

Nebulette Expression Is Associated with Lymph Node Metastasis in Patients with Colorectal Cancer.

BACKGROUND Colorectal cancer (CRC) is one of the most common cancers among men and women worldwide. Cancer metastasis is the main cause of death in patients with cancer. NEBL (nebulette, Gene ID: 10529) protein interacts with thin filaments in the cell and may functionally destabilize focal adhesion composition. There are some studies on NEBL gene expression alteration in cancer. In the presented study we aimed to analyze NEBL gene expression in patients with colorectal cancer to explore possible association of this gene with clinicopathological features in CRC. METHODS Sixty-seven fresh samples of colorectal tumors and adjacent normal tissues were collected from Iranian patients with CRC. Real time polymerase chain reaction was performed to measure the level of NEBL gene expression and its association with clinico-pathological features. RESULTS A significant overexpression with 3 fold increse was seen in NEBL mRNA level in tumoral tissues compared with the adjacent normal tissues. In addition there was a significant association between NEBL gene expression with lymph node metastasis in patients with CRC. CONCLUSION The overexpression of NEBL has the capacity to be considred as a prognostic biomarker in patients with CRC.

Prognostic and clinicopathological value of p16 protein aberrant expression in colorectal cancer: A PRISMA-compliant Meta-analysis.

Purpose:Several studies have examined the potential role of p16 protein expression as a diagnostic and prognostic biomarker in various cancers. However, it remains unclear whether p16 protein expression is a prognostic and diagnostic factor for colorectal cancer. Therefore, this meta-analysis is conducted to evaluate the associations of p16 protein expression with overall survival (OS) and clinicopathological characteristics of colorectal cancer.Methods:According to PRISMA guideline, relevant literatures were identified by searching Medicine, Web of Science, WanFang, and CNKI databases. The pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were extracted from included studies to assess the association between p16 protein expression and OS of patients with colorectal cancer. Other relevant data were extracted to evaluate the correlations of p16 protein expression with risk and clinicopathological characteristics of colorectal cancer. Stata 12.0 software was applied to calculate the strength of association between p16 protein expression and colorectal cancer.Results:Forty-one studies were included to evaluate the association between p16 protein expression and colorectal cancer. Nine studies involving 1731 patients with colorectal cancer found that there was no association between p16 protein expression and OS of colorectal cancer in the overall analysis (HR = 0.78, 95% CI: 0.55–1.10). However, p16 protein overexpression was significantly associated with a better prognosis in patients with colorectal cancer when cut-off value of p16 protein expression was <10% (HR = 0.23, 95% CI: 0.08–0.66). The results of subgroup analysis based on ethnicity indicated that p16 protein overexpression was a risk factor for the occurrence of colorectal cancer in Caucasians (odds ratio = 28.95, 95% CI: 6.08–137.89), but not in Asians. Furthermore, p16 protein overexpression was significantly associated with the Dukes stage, lymph node metastasis, tumor location, and Tumor Lymph Node Metastasis-stage of colorectal cancer.Conclusions:p16 protein overexpression might be a useful biomarker to predict the clinicopathological progress and prognosis of colorectal cancer.

Expressions and clinical significances of Eag1 and VEGF in colorectal cancer tissues

Objective To study the expressions of Eag1 and vascular endothelial growth factor (VEGF) in colorectal cancer, and to explore the relationships between Eag1 and VEGF expressions and clinicopathologic features of colorectal cancer. The correlation between Eag1 and VEGF and their clinical significance in colorectal cancer were explored. Methods A total of 73 cases of colorectal cancer tissues, 25 cases of colorectal adenoma and 10 cases of normal colorectal mucosa from January 2015 to December 2016 in Hunan Provincial People′s Hospital were collected. The expressions of Eag1, VEGF protein and mRNA in 73 cases of colorectal cancer tissues, 25 cases of colorectal adenoma and 10 cases of normal colorectal mucosa were detected by immunohistochemistry and real-time fluorescence quantitative polymerase chain reaction (RT-qPCR). The relationships between the two factors and the clinical pathological features of patients with colorectal cancer were analyzed. Results Immunohistochemistry showed that the positive rate of Eag1 in colorectal cancer group was 86.30% (63/73), which was significantly higher than that in colorectal adenoma group (20.00%, 5/25) and normal colorectal mucosa group (10.00%, 1/10), with significant differences (χ2=38.539, P<0.001; χ2=24.874, P<0.001). The positive rate of VEGF in colorectal cancer group was 89.04% (65/73), which was significantly higher than that in colorectal adenoma group (56.00%, 14/25) and normal colorectal mucosa group (30.00%, 3/10), with significant differences (χ2=10.980, P<0.001; χ2=16.911, P<0.001). There was a significant positive correlation between Eag1 and VEGF in colorectal cancer and colorectal adenoma tissues (c=0.580, P=0.010; c=0.669, P<0.001). The results of RT-qPCR showed that the expressions of Eag1 and VEGF mRNA in colorectal cancer group, colorectal adenoma group and normal colorectal mucosa group were 4.50±0.34, 3.14±0.44; 1.42±0.22, 1.61±0.15 and 1.00±0.16, 1.00±0.53, respectively, and the differences were statistically significant (F=15.546, P=0.014; F=5.363, P=0.025). The relative expression levels of Eag1 and VEGF mRNA in colorectal cancer group was about 4.50 times (t=31.851, P=0.003) and 3.14 times (t=6.870, P=0.014) than those in normal colorectal mucosa group. The mRNA expression levels of Eag1 and VEGF in colorectal cancer were correlated with degree of differentiation (F=840.725, P<0.001; F=102.950, P<0.001), depth of invasion (t=4.754, P<0.001; t=8.557, P<0.001), Duke staging (F=179.902, P<0.001; F=55.911, P<0.001) and lymph node metastasis (t=20.337, P<0.001; t=25.218, P<0.001). But they were not related to age (t=0.196, P=0.845; t=0.534, P=0.595) and sex (t=0.409, P=0.684; t=1.078, P=0.285). Conclusion Eag1 and VEGF are highly expressed in colorectal cancer tissues with positive correlation, and are closely related to the degree of differentiation, depth of invasion, Duke staging and lymph node metastasis of colorectal cancer. Both of them play important roles in the occurrence and development of colorectal cancer, which is expected to provide favorable research directions to the early diagnosis, treatment and prognosis of colorectal cancer. Key words: Colorectal neoplasms; Vascular endothelial growth factors; Eag1

Analysis of correlation between RASSF2A gene methylation and colorectal cancer

Objective To investigate the methylation status of RASSF2A gene promoter in colorectal cancer tissues and its correlation with the occurrence of colorectal. Methods From February 2007 to March 2013, a total of 111 cases of sporadic colorectal cancer patients were selected. The methylation status of RASSF2A gene in tumor tissue and normal mucosa were detected by using combined bisulfite restriction endonuclease method (COBRA). The correlations between the methylation of RASSF2A gene and the clinicopathologic features of colorectal cancer were analyzed. Results Methylation of RASSF2A gene was found in 83.78% (93/111) and 7.21% (8/111) of colorectal cancer tissues and normal tissues, with statistically significant difference (χ2=131.245, P<0.001). The methylation of RASFF2A gene was not correlated with histology type (χ2=3.554, P=0.314), Duke staging (χ2=3.217, P=0.359) and location of tumor (χ2=1.060, P=0.303). Conclusion The presence of RASSF2A hypermethylation in colorectal cancer may be associated with the occurrence of colorectal cancer. Key words: Colorectal neoplasms; DNA methylation; RASSF2A gene

Prognostic Value of FBXO39 and ETS-1 but not BMI-1 in Iranian Colorectal Cancer Patients

Background:Colorectal cancer (CRC) is one of the most prevalent cancers worldwide. Despite recent progress in diagnosis and treatment, it remains a major health problem and further studies are needed. We here investigated expression profiles of the FBXO39, ETS-1 and BMI-1 genes in CRCs to validate any possible diagnostic/prognostic significance.Material and Methods:Thirty six patients with locally advanced CRC admitted to Hazrate-Rasoul Hospital-Tehran were enrolled. Initially the expression pattern of FBXO39, ETS-1 and BMI-1 genes were determined using RT-PCR in CRC tumor and adjacent normal tissues then real-time RT-PCR was employed to quantify BMI-1 gene expression.Results:FBXO39 expression was restricted to tumor tissues. Interestingly, expression of this gene was detected in all stage-0 tumor samples. There was a significant relation between FBXO39 gene expression and lymph node involvement. The ETS-1 gene was expressed in 66% of all tumor tissues with p-value=0.03 for increase as compared to the adjacent normal samples. In addition, there was a significant relation between ETS-1 gene expression and tumor size and lymph node involvement. RT-PCR demonstrated BMI-1 gene expression in both tumor and normal tissues and quantification by real-time RT-PCR showed no association between BMI-1 levels and CRC clinicopathological features.Conclusion:Expression of FBXO39 and ETS-1 with lymph node involvement may be considered as an alarm for the occurrence of CRC metastasis, and therfore have prognostic value while BMI-1 appears without importance.

Expression of EZH2 is associated with poor outcome in colorectal cancer.

Enhancer of zeste homolog 2 (EZH2), the critical component of polycomb group protein family, has been demonstrated to be overexpressed in various types of human cancer, including hepatocellular carcinoma, breast, bladder and lung cancer. The mechanism of how EZH2 promotes oncogenesis has also been well studied. However, little is known about the role of EZH2 in colorectal cancer (CRC). The main purpose of the present study was to analyze the association between EZH2 expression and the clinicopathological features of CRC. Therefore, the mRNA and protein expression levels were analyzed in tumor tissues and adjacent non-cancerous tissues by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis. The expression of EZH2 was demonstrated to be significantly increased in tumor tissues compared with adjacent noncancerous tissues, according to the results of western blot analysis and RT-qPCR in the majority of cases. Patients with low EZH2 expression had a longer overall survival rate compared with those with high EZH2 expression. An analysis of the association between clinicopathological features and EZH2 expression indicated that high EZH2 expression was significantly associated with tumor stage, tumor size, histological differentiation and lymph node metastasis. Multivariate analysis demonstrated that high EZH2 expression was an independent predictor of overall survival. In conclusion, to the best of our knowledge, the data presented in the present study is the first to indicate that EZH2 is upregulated in CRC and may serve as a predictor of poor outcome for patients with CRC.

Mitochondrial UQCRB as a new molecular prognostic biomarker of human colorectal cancer

Ubiquinol cytochrome c reductase binding protein (UQCRB) is important for mitochondrial complex III stability, electron transport, cellular oxygen sensing and angiogenesis. However, its potential as a prognostic marker in colorectal cancer (CRC) remains unclear. The aim of this study was to determine whether UQCRB can be used as a diagnostic molecular marker for CRC. The correlation between the expression of three genes (UQCRB, UQCRFS1 and MT-CYB) in the mitochondrial respiratory chain complex III and clinico-pathological features was determined. Compared to non-tumor tissues, UQCRB gene expression was upregulated in CRC tissues. Gene and protein expression of the genes were positively correlated. Copy number variation (CNV) differences in UQCRB were observed in CRC tissues (1.32-fold) compared to non-tumor tissues. The CNV of UQCRB in CRC tissues increased proportionally with gene expression and clinical stage. Single-nucleotide polymorphisms in the 3′-untranslated region of UQCRB (rs7836698 and rs10504961) were investigated, and the rs7836698 polymorphism was associated with CRC clinical stage. DNA methylation of the UQCRB promoter revealed that most CRC patients had high methylation levels (12/15 patients) in CRC tissues compared to non-tumor tissues. UQCRB overexpression and CNV gain were correlated with specific CRC clinico-pathological features, indicating clinical significance as a prognostic predictor in CRC. Gene structural factors may be more important than gene transcription repression factors with respect to DNA methylation in UQCRB overexpression. Our results provide novel insights into the critical role of UQCRB in regulating CRC, supporting UQCRB as a new candidate for the development of diagnostics for CRC patients.