Phosphorylation of TFCP2L1 by CDK1 is required for stem cell pluripotency and bladder carcinogenesis.

Jinbeom Heo,Yong Mee Cho,Chae‐Min Ryu,Hwangkyo Jeong,Peter Cw Lee,Yumi Oh,Hyein Ju,Hwan Yeul Yu,Hye‐Yeon Lee,Jong Soo Kim,Bumsik Hong,Byeong‐Joo Noh,Seungun Lee,Jisun Lim,Jaekyoung Son,Dong‐Myung Shin,Sang‐Yeob Kim,Kyunggon Kim,Yonghwan Kim

doi:10.15252/emmm.201910880

Abstract

Molecular programs involved in embryogenesis are frequently upregulated in oncogenic dedifferentiation and metastasis. However, their precise roles and regulatory mechanisms remain elusive. Here, we showed that CDK1 phosphorylation of TFCP2L1, a pluripotency‐associated transcription factor, orchestrated pluripotency and cell‐cycling in embryonic stem cells (ESCs) and was aberrantly activated in aggressive bladder cancers (BCs). In murine ESCs, the protein interactome and transcription targets of Tfcp2l1 indicated its involvement in cell cycle regulation. Tfcp2l1 was phosphorylated at Thr177 by Cdk1, which affected ESC cell cycle progression, pluripotency, and differentiation. The CDK1‐TFCP2L1 pathway was activated in human BC cells, stimulating their proliferation, self‐renewal, and invasion. Lack of TFCP2L1 phosphorylation impaired the tumorigenic potency of BC cells in a xenograft model. In patients with BC, high co‐expression of TFCP2L1 and CDK1 was associated with unfavorable clinical characteristics including tumor grade, lymphovascular and muscularis propria invasion, and distant metastasis and was an independent prognostic factor for cancer‐specific survival. These findings demonstrate the molecular and clinical significance of CDK1‐mediated TFCP2L1 phosphorylation in stem cell pluripotency and in the tumorigenic stemness features associated with BC progression.

Highlights

Molecular programs involved in embryogenesis are frequently upregulated in oncogenic dedifferentiation and metastasis
By analyzing the immunoprecipitation (IP) products of FLAG-tagged Tfcp2l1 in murine embryonic stem cells (ESCs), we confirmed that Tfcp2l1 interacted with several proteins related to pluripotency (Oct-4, SOX-2, Nanog, and Klf4), the nucleosome remodeling deacetylase complex, and the transformation/transcription domain-associated protein (Trrap)/ p400 complex (including RuvB-like 2 (Ruvbl2), histone acetyltransferase KAT5 (Tip60), and DNA methyltransferase 1-associated protein 1 (DNMAP-1); Fig EV1A)
When T24 cells with overexpression or silencing of Transcription factor CP2-like protein 1 (TFCP2L1) were seeded on low attachment plates at clonogenic densities, followed by a 1-week culture period, we found that TFCP2L1-silenced T24 bladder cancers (BCs) cells hardly produced tumor spheres with sharp edges; ectopic expression of TFCP2L1 or its coexpression with cyclin-dependent kinase 1 (CDK1) increased tumor sphere formation in comparison with cells transfected with the empty control (Fig 5F)

Summary

Introduction

Molecular programs involved in embryogenesis are frequently upregulated in oncogenic dedifferentiation and metastasis. Their precise roles and regulatory mechanisms remain elusive. In patients with BC, high co-expression of TFCP2L1 and CDK1 was associated with unfavorable clinical characteristics including tumor grade, lymphovascular and muscularis propria invasion, and distant metastasis and was an independent prognostic factor for cancer-specific survival. These findings demonstrate the molecular and clinical significance of CDK1mediated TFCP2L1 phosphorylation in stem cell pluripotency and in the tumorigenic stemness features associated with BC progression

Objectives

Methods

Results

Conclusion