Dataset Information

Inhibition of EZH2 expression is associated with the proliferation, apoptosis and migration of SW620 colorectal cancer cells in vitro.

ABSTRACT: Epigenetic changes have been recently recognized as important in many human cancers. Enhancer of zeste homologue 2 (EZH2) gene has shown overexpression in various human cancers, consistent with a straightforward role of EZH2 as an oncogene, but its function in carcinogenesis is partly contradictory. The role of EZH2 in development of human colorectal cancer (CRC) has not yet been clarified. In present study, we observed up-regulation of EZH2 expression in tumor tissues from CRC patients. The expression of EZH2 in CRC cell lines is consistent with the trend in cancer tissues using RT-PCR. We showed that TNM stage and lymph node metastasis in CRC patients are significantly correlated with EZH2 expression levels. EZH2 level of transcription and protein was inhibited by small interfering RNA (siRNA). More importantly, EZH2-siRNA inhibited the proliferation and migration of SW620 cells while promoting their apoptosis, and inducing G0/G1 cell cycle arrest of CRC cells. Collectively, our results suggest that up-regulated EZH2 expression may contribute to the progression of the patients with CRC. A comprehensive study of epigenetic mechanisms and the relevance of EZH2 in CRC is important for fully understanding this disease and as a basis for developing new treatment options in patients with CRC.

SUBMITTER: Song-Bing H

PROVIDER: S-EPMC4935376 | biostudies-other | 2015 Apr

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Inhibition of EZH2 expression is associated with the proliferation, apoptosis and migration of SW620 colorectal cancer cells in vitro.

Song-Bing He H Hao Zhou Z Jian Zhou Z Guo-Qiang Zhou Z Tuo Han H Dai-Wei Wan W Wen Gu G Lin Gao G Yi Zhang Z Xiao-Feng Xue X Li-Feng Zhang Z Min Fei F Shui-Qing Hi H Xiao-Dong Yang Y Xin-Guo Zhu Z Liang Wang W De-Chun Li L

Experimental biology and medicine (Maywood, N.J.) 20150227 4

Epigenetic changes have been recently recognized as important in many human cancers. Enhancer of zeste homologue 2 (EZH2) gene has shown overexpression in various human cancers, consistent with a straightforward role of EZH2 as an oncogene, but its function in carcinogenesis is partly contradictory. The role of EZH2 in development of human colorectal cancer (CRC) has not yet been clarified. In present study, we observed up-regulation of EZH2 expression in tumor tissues from CRC patients. The exp ...[more]

PMID: 25724194

Similar Datasets

Project description:PurposeTo investigate the effect of urocortin-1 (UCN-1) on growth, migration, and apoptosis in colorectal cancer (CRC) in vivo and vitro and the mechanism by which UCN-1 modulates CRC cells in vitro.MethodsThe correlation between UCN-1 and CRC was evaluated using The Cancer Genome Atlas (TCGA) database and a tissue microarray. The expression of UCN-1 in CRC cells was assessed using quantitative real-time polymerase chain reaction (RT-qPCR) and western blotting. In vitro, the influence of UCN-1 on the proliferation, apoptosis, and migration of HT-29, HCT-116, and RKO cells was explored using the celigo cell counting assay or cell counting kit-8 (CCK8), flow cytometry, and wound healing or Transwell assays, respectively. In vivo, the effect of UCN-1 on CRC growth and progression was evaluated in nude mice. The downstream pathway underlying UCN-1-mediated regulation of CRC was determined using the phospho-kinase profiler array in RKO cells. Lentiviruses were used to knockdown or upregulate UCN-1 expression in cells.ResultsBoth the TCGA and tissue microarray results showed that UCN-1 was strongly expressed in the tissues of patients with CRC. Furthermore, the tissue microarray results showed that the expression of UCN-1 was higher in male than in female patients, and high expression of UCN-1 was associated with higher risk of lymphatic metastasis and later pathological stage. UCN-1 knockdown caused a reduction in CRC cell proliferation, migration, and colony formation, as well as an increase in apoptosis. In xenograft experiments, tumors generated from RKO cells with UCN-1 knockdown exhibited reduced volumes and weights. A reduction in the expression of Ki-67 in xenograft tumors indicated that UCN-1 knockdown curbed tumor growth. The human phospho-kinase array showed that the p53 signaling pathway participated in UCN-1-mediated CRC development. The suppression in migration and proliferation caused by UCN-1 knockdown was reversed by inhibitors of p53 signal pathway, while the increase in cell apoptosis was suppressed. On the other hand, overexpression of UCN-1 promoted proliferation and migration and inhibited apoptosis in CRC cells. Overexpression of p53 reversed the effect of UCN-1 overexpression on CRC development.ConclusionUCN-1 promotes migration and proliferation and inhibits apoptosis via inhibition of the p53 signaling pathway.

Project description:Signal transducer and activator of transcription 3 (STAT3), a transcriptional factor involved in tumorigenesis and cancer stemness formation, contributes to drug resistance in cancer therapies. STAT3 not only mediates gene transcription but also participates in microRNA suppression. This study identified a STAT3-downstream micro RNA (miRNA) involved in drug resistance against regorafenib in colorectal cancer stem-like tumorspheres. Small RNAseq was used to investigate differential microRNAs in colorectal cancer cell-derived tumorspheres and in a STAT3-knockdown strain. The miRNA-mediated genes were identified by comparing RNAseq data with gene targets predicted using TargetScan. Assays for detecting cell viability and apoptosis were used to validate findings. The formation of colorectal cancer stem-like tumorspheres was inhibited by BBI608, a STAT3 inhibitor, but not by regorafenib. Additional investigations for microRNA expression demonstrated an increase in 10 miRNAs and a decrease in 13 miRNAs in HT29-derived tumorspheres. A comparison of small RNAseq results between tumorspheres and HT29shSTAT3 cells revealed the presence of four STAT3-mediated miRNAs in HT29-derived tumorspheres: hsa-miR-215-5p, hsa-miR-4521, and hsa-miR-215-3p were upregulated, whereas miR-30a-5p was downregulated. Furthermore, hsa-miR-4521 was associated with poor overall survival probability, and miR-30a-5p was associated with better overall survival probability in patients with rectum cancer. Comparisons of RNAseq findings between HCT116- and HT29-derived tumorspheres revealed that HSPA5 were mediated by the STAT3-miR-30a-5p axis, which is overexpressed in colorectal tumorspheres associating to anti-apoptosis. In addition, the transfection of miR-30a-5p and inhibition of HSPA5 by HA15 significantly reduced cell viability and increased apoptosis in HT29 cells. In conclusion, a STAT3-miR-30a-5p-HSPA5 axis was observed against regorafenib-mediated apoptosis in colorectal cancer tumorspheres. The expression of miR-30a-5p was repressed by STAT3; in addition, HSPA5 was identified as the target gene of miR-30a-5p and contributed to both tumorsphere formation and anti-apoptosis.

Project description:Kruppel like factor 6 (KLF6), a member of KLF family, which has classic zinc finger structure, is broadly considered to have anticancer activity. The role of SV2 variant, one of KLF6 alternative splicing isoforms has not yet been definite in the colorectal cancer. This study aimed to detect the expression of the KLF6-SV2 in colorectal cancer and investigate its impact on cell proliferation and apoptosis. qRT-PCR was used to quantitatively determine KLF6-SV2 mRNA expression in colorectal cancer samples, corresponding normal tissue, normal colonic mucosal cell line FHC and seven colorectal cancer cell lines. SW480 and SW620 cell models with over-expressing KLF6-SV2 were constructed. Cell proliferation, cell cycle and apoptosis were measured respectively using MTT assay, DNA ploidy detection and Annexin V flow cytometry. Meanwhile, expression of p53, p21 and Bax were detected by qRT-PCR and western blot. The mRNA expression level of KLF6-SV2 in colorectal cancer tissues (0.783±0.409) was decreased than in corresponding normal tissues (1.086±0.449) (P<0.01), and expression in SW480 and SW620 were lower than in FHC, HCT116, LoVo, HT29, Caco-2 and RKO. In cell lines over-expressing KLF6-SV2, cell proliferation was markedly suppressed, cell cycle was blocked and cell apoptosis was significantly induced. Simultaneously, expression of p21 and Bax were remarkably up-regulated, while p53 remained unchanged. Decreased expression of KLF6-SV2 may be associated with the occurrence and development of colorectal cancer. KLF6-SV2 plays a role as tumor suppressor by efficiently blocking cell proliferation, arresting cell cycle and inducing apoptosis in colorectal cancer, which may be related to increased expression of p21 and Bax.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal. http://creativecommons.org/licenses/by-nc-nd/4.0/.

Dataset Information

Inhibition of EZH2 expression is associated with the proliferation, apoptosis and migration of SW620 colorectal cancer cells in vitro.

Publications

Inhibition of EZH2 expression is associated with the proliferation, apoptosis and migration of SW620 colorectal cancer cells in vitro.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets