Normal Colorectal Cancer Tissues Research Articles

A Prognostic Model Based on the Immune-Related lncRNAs in Colorectal Cancer

BackgroundColorectal cancer (CRC) is one of the most common malignant tumors with a poor prognosis. At present, the pathogenesis is not completely clear. Therefore, finding reliable prognostic indicators for CRC is of important clinical significance. In this study, bioinformatics methods were used to screen the prognostic immune-related lncRNAs of CRC, and a prognostic risk scoring model based on immune-related lncRNAs signatures were constructed to provide a basis for prognostic evaluation and immunotherapy of CRC patients.MethodsThe clinical information and RNA-seq data of CRC patients were obtained from The Cancer Genome Atlas (TCGA) database. The information of immune-related lncRNA was downloaded from the immunology database and analysis portal. The differentially expressed immune-related lncRNAs (IRLs) were screened by the edgeR package of R software. The prognostic value of IRLs was studied. Based on Cox regression analysis, a prognostic index (IRLPI) based on IRLs was established, and the relationship between the risk score and the clinicopathological characteristics of CRC was analyzed to determine the effectiveness of the risk score model as an independent prognostic factor.ResultsA total of 240 differentially expressed IRLs were identified between normal colorectal cancer tissues and normal colorectal cancer tissues, in which 8 were significantly associated with the survival of CRC patients (P < 0.05), including LINC00461, LINC01055, ELFN1-AS1, LMO7-AS1, CYP4A22-AS1, AC079612.1, LINC01351, and MIR31HG. And most of the lncRNAs related to survival were risk factors for the prognosis of CRC. The index established based on the 7 survival-related IRLs found to be highly accurate in monitoring CRC prognosis. Besides, IRLPI was significantly correlated with a variety of pathological factors and immune cell infiltration.ConclusionEight immune-related lncRNAs closely related to the prognosis of CRC patients were identified from the TCGA database. At the same time, an independent IRLPI was constructed, which may be helpful for clinicians to assess the prognosis of patients with CRC and to formulate individualized treatment plans.

The Effects of TRAF6 on Growth and Progression in Colorectal Cancer are Regulated by miRNA-140.

Background and AimSome studies have confirmed that miRNA-140 exhibits a suppressive role in gastric cancer, Wilms’ tumor. However, the function of miRNA-140 in colorectal cancer has not been completely elucidated. The present study aims to verify TRAF6 as the targeted gene by miRNA-140 which was investigated in colorectal cancer tissues and cells, and its effects on the biological characteristics of colorectal cancer cells were determined, in order to provide an experimental and theoretical basis for the application of TRAF6 in the treatment of colorectal cancer.MethodsqPCR analyzed miRNA-140 expression levels in colorectal cancer tissues, normal colorectal cancer tissues and colorectal cells including SW480 and HCT116 cancer cells and FHC normal colorectal epithetical cells. A serial biological experiment analyzed miRNA-140 effects on cell proliferation, migration and invasion capacities in SW480 and HCT116 cells. miRNA targeting gene prediction and a dual luciferase assay were used to analyze miRNA-140-targeted TRAF6. qPCR and Western blot analyzed miRNA-140 effects on the mRNA and protein expression of TRAF6. Western blot analyzed miRNA-140 effects on NF-κB/c-jun signaling pathways. Animal studies were performed to investigate the effects of miRNA-140 on colorectal cancer implantation tumor growth. Immunohistochemistry analyzed TRAF6 expression in animal experimentation tumors.ResultsmiRNA-140 expression is lower in colorectal cancer tissues and colorectal cancer cells. Over-expression of miRNA-140 inhibited the proliferation, migration and invasion capacities of colorectal cancer cells. miRNA-140 targeted the TRAF6 mRNA 3ʹUTR area and decreased TRAF6 protein expression. miRNA-140 suppressed p-NF-κB/p-c-jun proteins expression. miRNA-140 inhibited colorectal cancer implantation tumor growth in the mice model.ConclusionmiRNA-140 targeting TRAF6 affects the progression and growth of colorectal cancer, the mechanism could be miRNA-140 decreasing the TRAF6 expression effects on the NF-κB/c-jun signaling pathways.

MiR-150-504-519d inhibits the growth of human colorectal cancer cell line SW48 and downregulates c-FLIP receptor.

microRNAs (miRNAs) are noncoding RNAs that regulates the expression of target messenger RNAs (mRNAs). c-FLIP is an inhibitor of cell apoptosis through inhibition of caspase 8. miR-150, miR-504, and miR-519d were related to cancer cell proliferation, invasion, and migration in colorectal cancer (CRC). However, the role of miR-150-504-519d in CRC has not been studied and the relationship between miR-150-504-519d and c-FLIP remains unclear. In this study, we found that c-FLIP was upregulated in CRC tissues, without detectable expression in normal CRC tissues. Using SW48 cell line, we further showed that miR-150-504-519d inhibited migration, invasion, and promoted apoptosis of SW48 cells. Moreover, in SW48 cell line transfected with miR-150-504-519d, the protein expression of c-FLIP was significantly lower compared with cells transfected with scramble. Our results demonstrated upregulation of c-FLIP in CRC, which was downregulated in SW48 cells after the transfection of miR-150-504-519d, suggesting that manipulation of miR-150-504-519d expression might be a novel approach for the treatment of colorectal cancer.

Studying the mechanism of PLAGL2 overexpression and its carcinogenic characteristics based on 3'-untranslated region in colorectal cancer

Pleomorphic adenoma gene like-2 (PLAGL2) is a zinc finger protein transcription factor, which is upregulated and serves an oncogenic function in multiple human malignancies, including colorectal cancer (CRC). First, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression levels of PLAGL2 in CRC tissues and normal tissues. Then, bioinformatics analysis, RT-qPCR, western blotting, luciferase reporter assays and RNA-binding protein immunoprecipitation assays were performed to explore whether the underlying mechanisms, including copy number variation (CNV), microRNAs (miRNAs/miRs) and RNA-binding proteins (RBPs) led to the abnormal expression of PLAGL2. Finally, cell counting kit-8 assays, Transwell assays and xenograft models were used to detect carcinogenesis-associated characteristics based on the 3′-untranslated region (3′-UTR) of PLAGL2. In the present study, PLAGL2 was revealed to be upregulated in CRC tissues compared with normal CRC tissues. CNV was one of the causes leading to the upregulation of PLAGL2. miRNA, including downregulated miR-486-5p, and RBPs, including upregulated human antigen R (HuR), were other key underlying causes. In addition, PLAGL2 3′-UTR was revealed to promote the progression of CRC in vitro and in vivo, and to regulate the expression of C-MYC and CD44. To conclude, these results suggested that high expression of PLAGL2 in CRC was associated with CNV, miR-486-5p and HuR expression, whose 3′-UTR may promote colon carcinogenesis and serve as a novel potential biomarker for CRC therapies.

Correlation of human epidermal growth factor receptor protein expression and colorectal cancer.

To investigate the correlation between human epidermal growth factor receptor (HER-2) protein expression and colorectal cancer (CRC) using a case-control study and meta-analysis. Tumor tissue specimens from 162 CRC patients were selected for the case group. Fifty cases were randomly selected, and normal CRC tissue at least 10 cm away from the tumor margins of these cases was used to generate the control group. The expression of the HER-2 protein in the 162 CRC tissue samples and the 50 adjacent normal mucosa tissue samples was detected via immunohistochemistry. The experimental data were analyzed using SPSS 18.0 software, and R software version 3.1.0 was utilized for further verification. The expression of HER-2 protein in the 162 CRC tissue samples was significantly higher than in the normal tissue specimens. The data showed that the expression of HER-2 in CRC was related to the Dukes' stage, the depth of invasion and lymph node metastasis. The HER-2-positive patients had lower 3- and 5-year OS rates than the HER-2-negative patients, but there was no significant difference. However, there was a statistically significant difference in the 3- and 5-year disease-free survival (DFS) rates of HER-2-positive and HER-2-negative patients. The results of the meta-analysis showed that the expression of HER-2 in CRC patients was statistically significantly increased over that of healthy people. The 3-year DFS rate in HER-2-positive patients was markedly lower than that in HER-2-negative patients. Down-regulation of HER-2 expression might be a dependable strategy for CRC therapy.

Abstract C18: Identification of epigenetically silenced tumor suppressor genes in colorectal cancer

Abstract Background: The importance of gene inactivation by promoter CpG island hypermethylation has encouraged the unearthing of silenced tumor suppressor genes (TSGs) in various cancers. We aimed to identify and examine novel methylation silenced TSGs in colorectal cancer (CRC). Method: We employed Oligonucleotide microarray to find changes in global gene expression of five colon cancer cell lines (HCT116, RKO, Colo320, SW480, and HT29) that were analyzed before and after treatment with the demethylating agent 5-aza-2′-Deoxycitidine (5-aza-dC), expression of the responding genes was compared with microarray expression data of CRC tissue samples. Five genes (ASPP1, GADD45B, LIFR, SCARA5, and THSD1), which had a putative 5′ CpG islands in their promoter, were subjected to methylation-specific PCR (MSP) using 13 colon cell lines and 23 paired tumor and normal CRC tissues. Result: Seventy-two genes were up-regulated in demethylated cell lines and were simultaneously down-regulated in primary colorectal carcinomas, including genes that were known to be frequently hypermethylated and silenced in CRC. Among 13 colon cancer cell lines, hypermethylation was identified for three of five candidate genes, LIFR (61%), SCARA5 (15%), and THSD1 (23%). The methylation status of LIFR, SCARA5, and THSD1 was subsequently investigated in 23 colorectal tumors, hypermethylation was detected in (87%), (17%), and (9%), respectively. Data from normal colorectal mucosa demonstrated that the observed promoter hypermethylation was cancer-specific in the latter two genes. Conclusion: The use of a refined microarray screening led to the identification of two TSGs affected by hypermethylation with a cancer-specific manner in CRC. SCARA5 and THSD1 may have a role in CRC tumorigenesis. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the Second AACR International Conference on Frontiers in Basic Cancer Research; 2011 Sep 14-18; San Francisco, CA. Philadelphia (PA): AACR; Cancer Res 2011;71(18 Suppl):Abstract nr C18.