NUCB1 Suppresses Growth and Shows Additive Effects With Gemcitabine in Pancreatic Ductal Adenocarcinoma via the Unfolded Protein Response

Yong-Qiang Hua; Ke Zhang; Jie Sheng; Zhou-Yu Ning; Ye Li; Wei-Dong Shi; Lu-Ming Liu

doi:10.3389/fcell.2021.641836

NUCB1 Suppresses Growth and Shows Additive Effects With Gemcitabine in Pancreatic Ductal Adenocarcinoma via the Unfolded Protein Response

Front Cell Dev Biol. 2021 Mar 29:9:641836. doi: 10.3389/fcell.2021.641836. eCollection 2021.

Authors

Yong-Qiang Hua^{1

2}, Ke Zhang^{1

2}, Jie Sheng^{1

2}, Zhou-Yu Ning^{1

2}, Ye Li^{1

2}, Wei-Dong Shi^{1

2}, Lu-Ming Liu^{1

2}

Affiliations

¹ Minimally Invasive Treatment Center, Fudan University Shanghai Cancer Center, Shanghai, China.
² Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.

Abstract

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer with poor patient prognosis. A cellular stress response mechanism called the unfolded protein response (UPR) has been implicated in PDAC progression. More recently, nucleobindin 1 (NUCB1), a calcium-binding protein, has been shown to control the UPR but its precise role in PDAC has not been explored. Here, we found that downregulation of NUCB1 was associated with poor prognosis in patients with PDAC. Functionally, NUCB1 overexpression suppressed pancreatic cancer cell proliferation and showed additive effects with gemcitabine (GEM) in vitro and in vivo. Moreover, by controlling ATF6 activity, NUCB1 overexpression suppressed GEM-induced UPR and autophagy. Last but not least, we uncovered METTL3-mediated m⁶A modification on NUCB1 5'UTR via the reader YTHDF2 as a mechanism for NUCB1 downregulation in PDAC. Taken together, our study revealed crucial functions of NUCB1 in suppressing proliferation and enhancing the effects of gemcitabine in pancreatic cancer cells and identified METTL3-mediated m⁶A modification as a mechanism for NUCB1 downregulation in PDAC.

Keywords: NUCB1; autophagy; m6A modification; pancreatic ductal adenocarcinoma; unfolded protein response.