NUPR1, a new target in liver cancer: implication in controlling cell growth, migration, invasion and sorafenib resistance

Abstract

Sorafenib, an oral multikinase inhibitor, is the only approved agent for the treatment of advanced hepatocellular carcinoma (HCC). However, its benefits are modest, and as its mechanisms of action remain elusive, a better understanding of its anticancer effects is needed. Based on our previous study results, we investigated here the implication of the nuclear protein 1 (NUPR1) in HCC and its role in sorafenib treatment. NUPR1 is a stress-inducible protein that is overexpressed in various malignancies, but its role in HCC is not yet fully understood. We found that NUPR1 expression was significantly higher in primary human HCC samples than in the normal liver. Knockdown of NUPR1 significantly increased cell sensitivity to sorafenib and inhibited the cell growth, migration and invasion of HCC cells, both in vitro and in vivo. Moreover, NUPR1 silencing influenced the expression of RELB and IER3 genes. Unsurprisingly, RELB and IER3 knockdown also inhibited HCC cell viability, growth and migration. Using gene expression profiling of HCC cells following stable NUPR1 knockdown, we found that genes functionally involved in cell death and survival, cellular response to therapies, lipid metabolism, cell growth and proliferation, molecular transport and cellular movement were mostly suppressed. Network analysis of dynamic gene expression identified NF-κB and ERK as downregulated gene nodes, and several HCC-related oncogenes were also suppressed. We identified Runt-related transcription factor 2 (RUNX2) gene as a NUPR1-regulated gene and demonstrated that RUNX2 gene silencing inhibits HCC cell viability, growth, migration and increased cell sensitivity to sorafenib. We propose that the NUPR1/RELB/IER3/RUNX2 pathway has a pivotal role in hepatocarcinogenesis. The identification of the NUPR1/RELB/IER3/RUNX2 pathway as a potential therapeutic target may contribute to the development of new treatment strategies for HCC management.

Targeting HSP90 with the small molecule inhibitor AUY922 (luminespib) as a treatment strategy against hepatocellular carcinoma

“…Immunohistochemical analyses were performed as previously reported . Two independent pathologists (AG and BB) evaluated the relative percentages of positive cells, as well as staining intensity.…”

“…Immunofluorescence analysis and cell transfection with specific nuclear protein 1 (NUPR1) and Mcl‐1 small interference RNAs (siRNAs) (Supporting Information Table S1) were performed as previously reported . Briefly, for immunofluorescence analysis, HCC cells were seeded in chamber slides and, after 24 h, treated with 100 nM of AUY922 for another 24 h. Cells were fixed, permeabilized and stained with primary anti‐NUPR1 antibody.…”

“…After 24 h of transfection, a cell viability assay, RNA extraction and quantitative Real‐Time PCR were performed as previously reported . Briefly, total RNA was extracted from cells using TRIzol reagent, and 1 μg of RNA was used for reverse transcription to generate cDNA.…”

Serum from Chronic Hepatitis B Patients Promotes Growth and Proliferation via the IGF-II/IGF-IR/MEK/ERK Signaling Pathway in Hepatocellular Carcinoma Cells

“…In addition, NUPR1 is activated by HBx protein and mediates the cell growth and survival of HBV-positive cells [33]. A recent study also confirmed that NUPR1 plays a critical role in the regulation of the tumor cell growth, tumor migration, and invasive capacity of HCC cells, suggesting its oncogenic role in HCC [34]. In the present study, we found that serum from CHB patients increased NUPR1 mRNA and protein expression and promoted IGF-II–induced NUPR1 mRNA and protein expression in HCC cells.…”

Single-cell RNA sequencing reveals an altered gene expression pattern as a result of CRISPR/cas9-mediated deletion of Gene 33/Mig6 and chronic exposure to hexavalent chromium in human lung epithelial cells

“…NUPR1 is a transcription regulator that mediates diverse cellular functions, including cell proliferation, hypotrophy, apoptosis, autophagy, DNA repair, and EMT (Gironella et al , 2009; Goruppi and Iovanna, 2010; Cano et al , 2011). NUPR1 has been implicated in a number of cancers (Cano et al , 2011; Grasso et al , 2015; Emma et al , 2016). Of interest, NUPR1 has recently been shown to be induced by Cr(VI) and to suppress acetylation of histone H4 at lysine 16 (Chen et al , 2016).…”