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.

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Objective. To assess the association between MUC expression levels in colorectal cancer (CRC) tissues and prognosis and investigate the associations between MUC expression levels and CRC clinicopathological characteristics. Methods. The PubMed, Embase, Cochrane Library, and Web of Science databases were searched from inception through September 13, 2019, to identify studies investigating the association between MUC expression levels in CRC tissues and prognosis. Pooled hazard ratios (HRs) or odds ratio (ORs) with 95% confidence intervals (CIs) were used to evaluate associations between MUC expression levels and prognosis or clinicopathological characteristics, respectively. The heterogeneity between studies was assessed by the I2 values, whereas the likelihood of publication bias was assessed by Egger’s linear regression and Begg’s rank correlation test. Results. Among 33 included studies (n=6032 patients), there were no associations between combined MUC phenotype expression levels and overall survival (OS) or disease-free survival (DFS)/relapse-free survival (RFS) in patients with CRC. In subgroup analyses, the upregulated MUC1 expression (HR=1.50; 95% CI, 1.29–1.74; P<0.00001) was associated with poor OS. However, the upregulated MUC2 expression (HR=0.64; 95% CI, 0.52–0.79; P<0.00001) was associated with better OS. Furthermore, a high level of MUC1 expression (HR=1.99; 95% CI, 0.99–3.99; P=0.05) was associated with shorter DFS/RFS. However, patients with a low level of MUC2 tumors showed better DFS/RFS than patients with a high level of MUC2 tumors (HR=0.71; 95% CI, 0.49–1.04; P=0.08; P=0.0.009, I2=67%) and MUC5AC expression (HR=0.56; 95% CI, 0.38–0.82; P=0.003) was associated with longer DFS/RFS. In addition, a high level of MUC1 expression was associated with CRC in the rectum, deeper invasion, lymph node metastasis, distant metastasis, advanced tumor stage, and lymphatic invasion. A high level of MUC2 expression had a protective effect. High secretion of MUC5AC is associated with colon cancer compared with rectal cancer. Conclusion. The protein expression of MUC1 might be a poor biomarker in colorectal cancer and might play a role in tumor transformation and metastasis. However, the protein expression of MUC2 expression might have a protective effect. Furthermore, randomized controlled trials (RCTs) of large patients are needed to confirm the results.

The apoptosis-stimulating protein of p53 (ASPP) family is a newly identified family protein including ASPP1, ASPP2 and inhibitor of ASPP (iASPP), by which the tumor protein 53 (TP53)-mediated apoptotic process is selectively regulated. Downregulation of ASPP1/ASPP2 and upregulation of iASPP were revealed to be associated with a poor prognosis and metastasis in several types of cancer. However, to the best of our knowledge, the expression of ASPP in colorectal cancer (CRC) has not previously been investigated. The present study analyzed ASPP expression in human CRC tissues with multiple clinical and pathological profiles. A total of 41 patients diagnosed with CRC were enrolled in the present study. The expression of ASPP was detected by immunohistochemistry, immunofluorescence and reverse transcription-quantitative polymerase chain reaction. In addition, the variation in ASPP expression was examined in a number of pathological groups. The associations among ASPP expression, and the expression of TP53, plasma carcinoembryonic antigen (CEA) levels and α-fetoprotein (AFP) levels were also investigated. ASPP1 and ASPP2 expression was significantly reduced, while iASPP expression was elevated in CRC samples compared with expression in adjacent non-cancerous tissues. Downregulation of ASPP1 was detected in the TP53-positive group compared with the TP53-negative group. The increase in iASPP expression was correlated with the grade of malignancy, but not with regional lymph node status or metastases. The expression of ASPP2 was negatively correlated with plasma CEA levels. The results of the present study, not only enrich CRC epidemic and pathological data, but also provide valuable indices for CRC clinical treatment and prognosis.

Background: A systematic analysis was conducted to clarify the relationship between miR-143/145 and the prognosis of colorectal cancer. Materials and methods: We searched four databases: PubMed, EMBASE, Web of Science, and the Cochrane Library. We extracted and estimated the hazard ratios for survival outcomes, which compared low and high expression levels of miR-143/145 in colorectal cancer patients in the available studies. Each individual hazard ratio was used to calculate the pooled hazard ratio. Results: A total of 17 articles including 5128 patients were ultimately included. The results showed that there was no significant difference between low expression and high expression of miR-143 in the overall survival of colon cancer patients. However, low expression of miR-143 was significantly associated with high event-free survival (hazard ratio (HR) 0.6; 95% confidence interval (CI) 0.40, 0.88). Low expression of miR-145 was associated with poor prognosis of patients (HR 1.92; 95% CI 1.45, 2.54); those with low expression of miR-145 were at 1.92-fold higher risk for short-term overall survival than those with high expression of miR-145. MiR-145 was an unfavorable factor for the prognosis of colorectal cancer. There were no significant differences between low expression of miR-145 and high expression of miR-143 in event-free survival. Conclusion: miR-143 and miR-145 have promising prognostic value for colorectal cancer. Low expression of miR-143 can predict high event-free survival, and low expression of miR-145 can predict poor overall survival.