Research Paper Volume 10, Issue 12 pp 3774—3793
A CREB1/miR-433 reciprocal feedback loop modulates proliferation and metastasis in colorectal cancer
- 1 Department of General Surgery, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
- 2 Shanghai Institute of Nutrition and Health, Chinese Academy of Sciences, Shanghai, China
Received: October 6, 2018 Accepted: November 15, 2018 Published: December 6, 2018
https://doi.org/10.18632/aging.101671How to Cite
Abstract
Increasing evidence has indicated the prognostic value of miR-433 across a series of malignancy types. However, the underlying mechanisms involved in cancer progression haven’t been sufficiently elucidated. In the present work, we found that miR-433 was downregulated in CRC tissues and cell lines. Ectopic expression of miR-433 obviously suppressed the proliferation, invasion and metastasis activity of CRC cells in vitro and in vivo. CREB1, CCAR1 and JNK1 were highly expressed and negatively correlated with miR-433 expression in CRC. CRC patients with higher expression of CREB1, CCAR1 or JNK1 presented a worse outcome relative to those with lower expression. CREB1 transactivated the expression of miR-433, and CREB1, CCAR1 and JNK1 simultaneously served as its targets, which in turn composed a feedback loop between CREB1 and miR-433. miR-433 blocked cell cycle progression and abolished EMT. Collectively, our study demonstrated the CREB1/miR-433 reciprocal feedback loop restrained the propagation, invasion and metastasis activities of CRC cells through abrogation of cell cycle progression and constraint of EMT.
Abbreviations
AKT: serine/threonine kinase 1; BCA: bicinchoninic acid; BSA: bovine serum albumin; CCAR1: cell division cycle and apoptosis regulator 1; CDK2: cyclin dependent kinase 2; cDNA: complementary DNA; c-Jun: Jun proto-oncogene (AP-1 transcription factor subunit); CRC: colorectal cancer; CREB1: cAMP regulatory element-binding protein 1; ChIP: chromatin immunoprecipitation; DFS: disease free survival; DMEM: Dulbecco’s modified Eagle’s medium; Egr-1: early growth response 1; EMT: epithelial-mesenchymal transition; FBS: fetal bovine serum; FFPE: formalin-fixed and paraffin-embedded; FOLFOX: 5-fluoro-2,4(1H, 3H)-pyrimidinedione, leucovorin, oxaliplatin; FOLFIRI: 5-fluoro-2,4(1H, 3H)-pyrimidinedione, leucovorin, irinotecan; H&E: hematoxylin and eosin; IHC: immunochemistry; JNK1: c-Jun N-terminal protein kinase 1; JNK2: c-Jun N-terminal protein kinase 2; KEGG: Kyoto Encyclopedia of Genes and Genomes; K-Ras: KRAS proto-oncogene GTPase; miR: microRNA; MMR: mismatch repair; MTT: methyl thiazolyl tetrazolium; NC: negative control; OD: optical density; OS: overall survival; p21: CDKN1A, cyclin dependent kinase inhibitor 1A; p27: CDKN1B, cyclin dependent kinase inhibitor 1B; p90Rsk: ribosomal protein S6 kinase A1, RPS6KA1; PBS: phosphate buffered solution; PDX: patient derived xenograft; PFS: progression free survival; PKA: protein kinase A; PMSF: phenylmethane sulfonyl fluoride; pTNM: pathological tumor lymph node metastasis; qRT-PCR: quantitative real-time PCR; RNAi: RNA intervention; RFS: relapse free survival; siRNA: small interference RNA; TGF: transforming growth factor; XELOX: xeloda, oxaliplatin; 5-FU: 5-fluoro-2,4(1H, 3H)-pyrimidinedione.