Interferon γ suppresses dentin sialophosphoprotein in oral squamous cell carcinoma cells resulting in antitumor effects, via modulation of the endoplasmic reticulum response

Abstract

The expression of proinflammatory cytokines in various malignant neoplasms is widely considered to represent the host immune response to tumor development. The role of interferon (IFN)γ in head and neck squamous cell carcinoma, and its association with endoplasmic reticulum (ER) stress pathways, remains a subject of ongoing investigation. Dentin sialophosphoprotein (DSPP), which is a member of the small integrin-binding N-linked glycoproteins family, has been implicated in malignant transformation and invasion of oral squamous cell carcinoma (OSCC). Recent studies have established matrix metalloproteinase (MMP)20 as the cognate MMP partner of DSPP. The present study examined the effects of IFNγ treatment on DSPP and MMP20 expression, ER stress, the unfolded protein response (UPR), and calcium (Ca) homeostasis regulatory mechanisms in OSCC cells. The OSC2 OSCC cell line was treated with IFNγ at specific time-points. At each time-point, the mRNA expression levels of DSPP and MMP20, and those of ER-stress-, UPR- and Ca homeostasis-associated proteins [78-kDa glucose-regulated protein (GRP78), sarco/endoplasmic reticulum Ca2+-ATPase (SERCA2b), inositol 1,4,5-trisphosphate receptor (IP3r), protein kinase R-like ER kinase (PERK) and inositol-requiring enzyme 1 (IRE1)], were assessed by reverse transcription-quantitative polymerase chain reaction. The protein expression levels of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), proliferating cell nuclear antigen (PCNA) and cytochrome c were analyzed by western blotting. Cell viability, apoptosis and migration were evaluated by MTT, Annexin V-fluorescein isothiocyanate flow cytometry and wound-healing assays, respectively. IFNγ treatment significantly downregulated the mRNA expression levels of the major ER stress regulator GRP78 and, to a lesser extent, the UPR-associated molecule IRE1; however, IFNγ had no significant effect on PERK. With regards to ER Ca homeostasis molecules, treatment with IFNγ downregulated the mRNA expression levels of SERCA2b and upregulated those of IP3r. Furthermore, DSPP and MMP20 mRNA expression levels were significantly reduced following IFNγ treatment. Notably, treatment with IFNγ hampered OSC2 migration, reduced cell viability and PCNA protein expression, enhanced apoptosis, downregulated Bcl-2, and upregulated Bax and cytochrome c. Overall, IFNγ inhibited OSCC cell viability and migration, and increased apoptosis, possibly by regulating ER stress and UPR mechanisms. In addition, IFNγ-induced DSPP and MMP20 downregulation may correspond with alteration in ER Ca homeostasis.

The Effects of IFN-γ and IL-4 Expression on PCNA Expression in Transplanted Bone Tumors

“…And PCNA was inhibited by IFN at the G1 stage of beginning proliferation. In addition, the VX2 tumor has a strong ability of proliferation and replication, which means that when the expression level of PCNA gradually increases, the tumor tissue will continue to proliferate, grow and invade the surrounding tissue [22][23].…”

Construction of an 11-microRNA-based signature and a prognostic nomogram to predict the overall survival of head and neck squamous cell carcinoma patients

“…We found that several targeted genes exert their functions through the neurotrophin signaling pathway, which performs key functions in the occurrence and development of HNSCC by regulating cell survival, angiogenesis, tissue invasion, DNA damage resistance, and epithelial-to-mesenchymal transition [ 27 – 30 ]. Gkouveris et al demonstrated that interferon-gamma inhibits OSCC cell viability and migration and increases cellular apoptosis through the endoplasmic reticulum stress pathway [ 31 ]. Further, dentin sialophosphoprotein induces OSCC cell viability [ 32 ] and HIV protease inhibitors with radiosensitizing activities mediate HNSCC cell apoptosis [ 33 ] through the activation of the endoplasmic reticulum stress mechanisms.…”

Calcium Ions Aggravate Alzheimer’s Disease Through the Aberrant Activation of Neuronal Networks, Leading to Synaptic and Cognitive Deficits

“…Through a more complicated mechanism, APOE4 induces neuronal apoptosis in APOE4 knockout mice by activating NMDAR-mediated Calcium/Calmodulin dependent protein kinase II (CaMKII) pathways (Qiao et al, 2017). Moreover, TBI induces apoptosis in the cortex and hippocampus of Tg mice overexpressing human APOE4 by activating APOE4 (Giarratana et al, 2020). In addition, ER stress also mediates the effects of the unfolded protein response (UPR) and misfolded proteins on inducing apoptosis through mechanisms related to Ca 2+ influx (Nishitoh et al, 2009;Moreno et al, 2013).…”

“…In SH-SY5Y cells, IFNγ also induces Ca 2+ influx by activating TRPM2, leading to the apoptosis of cultured neurons (Sama et al, 2012 ). Furthermore, IFNγ reduces the activity of ATPase Sarcoplasmic/Endoplasmic Reticulum Ca 2+ Transporting 2b (SERCA2b) in IL-1β-stimulated OSCC cells (Cardozo et al, 2005 ; Gkouveris et al, 2018 ). In addition to these cytokines, inflammatory factors, such as H 2 O 2 , increase TRPM2 activity, which might lead to increased basal Ca 2+ levels in cultured rat microglial cells (Kraft et al, 2004 ).…”