ER resident protein 44 promotes malignant phenotype in nasopharyngeal carcinoma through the interaction with ATP citrate lyase

Abstract

Background Nasopharyngeal carcinoma (NPC) is one of the most common malignancy in head and neck. With the development of treatments, the prognosis has improved these years, but metastasis is still the main cause of treatment failure. The endoplasmic reticulum (ER) resident protein 44 is a UPR-induced ER protein of the protein disulphide isomerase (PDI) family. This study investigated the role of ERp44 in NPC progression. Methods Firstly, immunohistochemistry, western blot and qRT-PCR were used to investigate the expression of ERp44 in NPC samples and cell lines. We analyzed 44 NPC samples for ERp44 expression and investigated the association between its expression level with clinicopathologic parameters. Then we took CCK8, Transwell migration assay and used the zebrafish model to access the role of ERp44 on the malignant phenotype in NPC cells. Secondly, we used co-IP to gain the proteins that interact with ERp44 and took proteomic analysis. Furthermore, we successfully constructed the mutant variants of ERp44 and found the interaction domain with ATP citrate lyase(ACLY). Lastly, we subcutaneously injected NPC cells into nude mice and took immunohistochemistry to exam the expression of ACLY and ERp44. Then we used western blot to detect the expression level of epithelial-mesenchymal transition (EMT) markers. Results In the present study, we found ERp44 was elevated in NPC tissues and correlated with clinical stages and survive state of the patients. In vitro, the downregulation of ERp44 in NPC cells (CNE2, 5-8F) could suppress cells proliferation and migration. After that, we recognized that ACLY might be a potential target that could interact with ERp44. We further constructed the mutant variants of ERp44 and found the interaction domain with ACLY. The promotion of ERp44 on cell migration could be inhibited when ACLY was knocked down. More importantly, we also observed that the interaction of ERp44 with ACLY, especially the thioredoxin region in ERp44 play a vital role in regulating EMT. Lastly, we found ERp44 was positively correlated with the expression of ACLY and could promote NPC cells growth in nude mice. Conclusion Our data indicated that ERp44 participates in promoting NPC progression through the interaction with ACLY and regulation of EMT.

lncRNA CYTOR promotes aberrant glycolysis and mitochondrial respiration via HNRNPC-mediated ZEB1 stabilization in oral squamous cell carcinoma

“…In addition, we used transparent in vivo imaging analysis of tumor metastasis [ 31 , 32 ] by microinjecting Dil-labeled, stably transfected oral cancer cell lines into the perivitelline space of Tg (fli-1: EGFP) zebrafish for 3 days to observe cell invasion (Fig. 1L ).…”

Exosomal ERp44 derived from ER-stressed cells strengthens cisplatin resistance of nasopharyngeal carcinoma

“…In our previous research, we have also reported that ERp44 was highly expressed in NPC and associated with patients' survive state and clinical stages, it also participated in promoting cells proliferation and migration [22]. However, the role of ERp44 on cell chemoresistance remains unclear.…”

Systematic Analysis of Molecular Subtypes and Immune Prediction Based on CD8 T Cell Pattern Genes Based on Head and Neck Cancer

“…ERP44 can not only regulate protein maturation and secretion but also participate in the modulation of calcium as well as redox homeostasis in the endoplasmic reticulum [ 26 , 27 ]. In nasopharyngeal carcinoma, the interaction between ERP44 and ACLY promotes the malignant phenotype of nasopharyngeal carcinoma cells [ 28 ]. In addition, ERP44 inhibits the migratory ability of lung cancer cells through IP3R2 [ 29 ].…”