NCAPG Induces Cell Proliferation in Cardia Adenocarcinoma via PI3K/AKT Signaling Pathway

Xinxin Zhang; Hui Wang; Yajuan Han; Mengqi Zhu; Zaozhi Song; Dankai Zhan; Jianguang Jia

doi:10.2147/OTT.S276868

NCAPG Induces Cell Proliferation in Cardia Adenocarcinoma via PI3K/AKT Signaling Pathway

Onco Targets Ther. 2020 Nov 4:13:11315-11326. doi: 10.2147/OTT.S276868. eCollection 2020.

Authors

Xinxin Zhang¹, Hui Wang¹, Yajuan Han², Mengqi Zhu¹, Zaozhi Song¹, Dankai Zhan¹, Jianguang Jia¹

Affiliations

¹ Department of Surgical Oncology, The First Affiliated Hospital of Bengbu Medical College, Bengbu 233000, People's Republic of China.
² Department of Medical Oncology, The First Affiliated Hospital of Bengbu Medical College, Bengbu 233000, People's Republic of China.

Abstract

Purpose: Previous studies have shown that non-SMC condensin I complex subunit G (NCAPG) overexpression is correlated to poor prognosis of multiple cancer types. Herein, we explored the underlying mechanism of NCAPG-mediated cardia adenocarcinoma (CA) proliferation and cell cycle regulation.

Methods: The protein profiling technology was used to analyze the gene expression in 20 CA and adjacent tissue samples. Differential genes were identified by bioinformatic analysis. Western blot and qRT-PCR-based analysis assessed the NCAPG expression levels in multiple CA cell lines. CA cell lines, SGC-7901 and AGS, were transfected with Lip 2000, and stably transfected cell lines were screened for NCAPG overexpression and downregulation. MTT and clone formation assays were employed to detect cell proliferation, and cell cycle phases were analyzed using flow cytometry. Western blot was performed to determine the NCAPG gene expression levels. Finally, we studied the tumorigenic effects of NCAPG in the mouse model and validated the cell experiment results using immunohistochemistry.

Results: A significant overexpression of NCAPG was found in CA tissues and CA cell lines. The outcomes of MTT and clone formation assays showed that NCAPG upregulation promoted cell proliferation. The outcomes of these analyses were further validated using nude mice as an in vivo tumor model. As per the outcome of Western blot and flow cytometry analysis, NCAPG regulated the G1 phase through the cyclins (CDK4, CDK6, and cyclin D1) overexpression and cell cycle inhibitors (P21 and P27) downregulation. Overexpressed NCAPG and silenced NCAPG, both in vitro and in vivo, resulted in abnormal activation of the PI3K/AKT signaling pathway in CA cells. We observed that NCAPG overexpression increased the levels of phosphorylated PI3K, AKT, and GSK3β; however, their total protein levels remained unchanged in CA cells.

Conclusion: As a CA oncogene, NCAPG promoted cell proliferation and regulated cell cycle through PI3K/AKT signaling pathway activation.

Keywords: NCAPG; PI3K/AKT pathway; cardia adenocarcinoma; cell cycle; proliferation.

Grants and funding

This study was supported by the Key Project of the Education Department of Anhui Province (KJ2017A240) and 2019 Bengbu Science and Technology Innovation Guidance Project and the 2019 College Student Innovation Training Program of Bengbu Medical College (Byycx1919).