Glycoprotein α-Subunit of Glucosidase II (GIIα) is a novel prognostic biomarker correlated with unfavorable outcome of urothelial carcinoma

Abstract

Background Urothelial carcinoma (UC) is among the most prevalent malignancies. The muscle-invasive bladder cancer (MIBC) shows an invasive feature and has poor prognosis, while the non-muscle invasive bladder cancer (NMIBC) shows a better prognosis as compared with the MIBC. However, a significant proportion (10%–30%) of NMIBC cases progress to MIBC. Identification of efficient biomarkers for the prediction of the course of UC remains challenging nowadays. Recently, there is an emerging study showed that post-translational modifications (PTMs) by glycosylation is an important process correlated with tumor angiogenesis, invasion and metastasis. Herein, we reported a data-driven discovery and experimental validation of GANAB, a key regulator of glycosylation, as a novel prognostic marker in UC. Methods In the present study, we conducted immunohistochemistry (IHC) assay to evaluate the correlation between the expression levels of GANAB protein and the prognosis of UC in our cohort of 107 samples using whole slide image (WSI) analysis. In vitro experiments using RNAi were also conducted to investigate the biological functions of GANAB in UC cell lines. Results We observed that positive GANAB protein expression was significantly correlated with poor prognosis of UC in our cohort, with p-value of 0.0017 in Log-rank test. Notably, tumor cells at the invasive front of the tumor margin showed stronger GANAB expression than the tumor cells inside the tumor body in UCs. We further validated that the elevated expression levels of GANAB were significantly correlated with high grade tumors (p-values of 1.72 × 10–10), advanced stages (6.47 × 10–6), and elevated in luminal molecular subtypes. Moreover, knocking-down GANAB using RNAi in UM-UC-3 and T24 cells inhibited cell proliferation and migration in vitro. Knockdown of GANAB resulted in cell cycle arrest at G1 phase. We demonstrated that GANAB mediated HIF1A and ATF6 transcriptional activation in the ER stress signaling, and regulated the gene expression of cell cycle-related transcriptional factors E2F7 and FOXM1. Conclusions The elevated expression of GANAB is a novel indicator of poorer prognosis of UC. Our data suggests that GANAB is not only a new and promising prognostic biomarker for UC, but also may provide important cues for the development of PTM-based therapeutics for UC treatment.

Current look at the most promising proteomic and glycomic biomarkers of bladder cancer

“…methods Refs. HOMER3 HOMER SCAFFOLD PROTEIN 3; HOMER3-19p13.11 MS Peixoto et al ( 2021 ) Fibronectin, laminin-5, and type IV collagen FIBRONECTIN 1; FN1-2q35 LAMININ, ALPHA-5; LAMA5-20q13.33 COL4A1-6; chromosomes 1, 2 and X SPRi Guszcz et al ( 2023 ) GANAB protein GLUCOSIDASE, ALPHA, NEUTRAL AB; GANAB-11q12.3 IHC Lin et al ( 2022 ) P4HB PROCOLLAGEN-PROLINE, 2-OXOGLUTARATE-4-DIOXYGENASE, BETA SUBUNIT; P4HB-17q25.3 Gene expression Wu et al ( 2021 ) Leukocyte differentiation antigen CD36 CD36 ANTIGEN; CD36-7q21.11 TMA, IHC Jeong et al ( 2021 ) CD93 (C1QR1) COMPLEMENT COMPONENT 1, q SUBCOMPONENT, RECEPTOR 1; C1QR1-20p11.21 Gene expression Zheng et al ( 2022 ) Cartilage oligomeric matrix protein (COMP) CARTILAGE OLIGOMERIC MATRIX PROTEIN; COMP-19p13.11 IHC, RT-qPCR Kuo et al ( 2022 ) Neurexophilin 4 NEUREXOPHILIN 4; NXPH4-12q13.3 Gene expression, IHC Sun et al ( 2022 ) Alpha-2-Heremans-Schmid Glycoprotein (AHSG) ALPHA-2-HS-GLYCOPROTEIN; AHSG-3q27.3 Cell proliferation assay, WB, ELISA, IHC Dong et al ( 2022 ) Fibulin-3 EGF-CONTAINING FIBULIN-LIKE EXTRACELLULAR MATRIX PROTEIN 1; EFEMP1-2p16.1 IHC Al Khader et al ( …”

“…107 FFPE samples and two cell lines were analyzed using immunohistochemistry (IHC) assay, and upregulated expression of GANAB was in correlation with high tumor grades, promoting proliferation, invasion, or migration of carcinoma cells. This protein can serve as a prognostic biomarker correlated with unfavorable outcomes of urothelial carcinoma (Lin et al 2022 ).…”

Glycosidase activated prodrugs for targeted cancer therapy

“…Cancer type b-Glucosidase Breast, 11 gastric, 12 liver 13 Glucosidase II Lung, 14 bladder, 15 gastric, 16 melanoma 17 N-Acetyl-b-Dglucosaminidase Ovarian, 18 liver, 19 leukemia, 19 thyroid, 20 breast 21 a-Glucosidase Liver, 19 leukemia 19 b-Galactosidase Liver, 19 ovarian, 22 prostate, 23 colon, 24 breast, 24 gliomas 25 b-Glucuronidase Lung, 26 breast, 27 ovarian, 28 pancreatic, 29 colorectal 30 a-Mannosidase Breast, 31 cervical, 32 clear cell renal carcinoma 33…”

ERVW-1 Activates ATF6-Mediated Unfolded Protein Response by Decreasing GANAB in Recent-Onset Schizophrenia

“…N-glycosylation is associated with ER stress, as the dysregulation of protein glycosylation can induce ER stress and activate the UPR [ 18 , 19 ]. Moreover, GANAB, which mediates ATF6 transcriptional activation, has been identified as a novel prognostic marker of urothelial carcinoma [ 20 ]. However, the relationship among GANAB, ATF6, and schizophrenia has not been reported, and there is insufficient evidence to establish a correlation between UPR and schizophrenia.…”