Dissection of Anti-tumor Activity of Histone Deacetylase Inhibitor SAHA in Nasopharyngeal Carcinoma Cells via Quantitative Phosphoproteomics

Huichao Huang; Ying Fu; Ye Zhang; Fang Peng; Miaolong Lu; Yilu Feng; Lin Chen; Zhuchu Chen; Maoyu Li; Yongheng Chen

doi:10.3389/fcell.2020.577784

Dissection of Anti-tumor Activity of Histone Deacetylase Inhibitor SAHA in Nasopharyngeal Carcinoma Cells via Quantitative Phosphoproteomics

Front Cell Dev Biol. 2020 Nov 26:8:577784. doi: 10.3389/fcell.2020.577784. eCollection 2020.

Authors

Huichao Huang¹, Ying Fu¹, Ye Zhang¹, Fang Peng¹, Miaolong Lu¹, Yilu Feng¹, Lin Chen^{2

3}, Zhuchu Chen^{1

4}, Maoyu Li^{1

4}, Yongheng Chen^{1

5}

Affiliations

¹ Department of Oncology, NHC Key Laboratory of Cancer Proteomics, XiangYa Hospital, Central South University, Changsha, China.
² Molecular and Computational Biology Program, Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States.
³ Department of Chemistry, University of Southern California, Los Angeles, CA, United States.
⁴ Department of Gastroenterology, XiangYa Hospital, Central South University, Changsha, China.
⁵ National Clinical Research Center for Geriatric Disorders, XiangYa Hospital, Central South University, Changsha, China.

Abstract

Suberoylanilide hydroxamic acid (SAHA), a pan HDAC inhibitor, has been approved by the Food and Drug Administration (FDA) to treat cutaneous T cell lymphoma (CTCL). Nevertheless, the mechanisms underlying the therapeutic effects of SAHA on tumors are yet not fully understood. Protein phosphorylation is one of the most important means to regulate key biological processes (BPs), such as cell division, growth, migration, differentiation, and intercellular communication. Thus, investigation on the impacts of SAHA treatment on global cellular phosphorylation covering major signaling pathways deepens our understanding on its anti-tumor mechanisms. Here we comprehensively identified and quantified protein phosphorylation for the first time in nasopharyngeal carcinoma (NPC) cells upon SAHA treatment by combining tandem mass tags (TMTs)-based quantitative proteomics and titanium dioxide (TiO₂)-based phosphopeptide enrichment. In total, 7,430 phosphorylation sites on 2,456 phosphoproteins were identified in the NPC cell line 5-8F, of which 1,176 phosphorylation sites on 528 phosphoproteins were significantly elevated upon SAHA treatment. Gene ontology (GO) analysis showed that SAHA influenced several BPs, including mRNA/DNA processing and cell cycle. Furthermore, signaling pathway analysis and immunoblotting demonstrated that SAHA activated tumor suppressors like p53 and Rb1 via phosphorylation and promoted cell apoptosis in NPC cells but inactivated energetic pathways such as AMPK signaling. Overall, our study indicated that SAHA exerted anti-tumor roles in NPC cells, which may serve as novel therapeutic for NPC patients.

Keywords: histone deacetylase; nasopharyngeal carcinoma; p53–Rb1 signaling pathway; quantitative phosphoproteomic; suberoylanilide hydroxamic acid.