Research Paper Volume 10, Issue 12 pp 3774—3793

A CREB1/miR-433 reciprocal feedback loop modulates proliferation and metastasis in colorectal cancer

Li Yan1, *,, Wei-Qiang You1, *,, Neng-Quan Sheng1, , Jian-Feng Gong1, , Lan-Dian Hu2, , Ge-Wen Tan1, , Hong-Qi Chen1, , Zhi-Gang Wang1, ,

  • 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
* Equal contribution

Received: October 6, 2018       Accepted: November 15, 2018       Published: December 6, 2018      

https://doi.org/10.18632/aging.101671
How to Cite

Copyright: Yan et al. This is an open‐access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

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.