ABSTRACT
Oral squamous cell carcinoma (OSCC) is the predominant histological type of the head and neck squamous cell carcinoma (HNSCC). By comparing the differentially expressed genes (DEGs) in OSCC-TCGA patients with copy number variations (CNVs) that we identify in OSCC-OncoScan dataset, we herein identified 37 dysregulated candidate genes. Among these potential candidate genes, 26 have been previously reported as dysregulated proteins or genes in HNSCC. Among 11 novel candidates, the overall survival analysis revealed that melanotransferrin (MFI2) is the most significant prognostic molecular in OSCC-TCGA patients. Another independent Taiwanese cohort confirmed that higher MFI2 transcript levels were significantly associated with poor prognosis. Mechanistically, we found that knockdown of MFI2 reduced cell viability, migration and invasion via modulating EGF/FAK signaling in OSCC cells. Collectively, our results support a mechanistic understanding of a novel role for MFI2 in promoting cell invasiveness in OSCC.
ABSTRACT
BACKGROUND: DNA copy number variations (CNVs) are a hallmark of cancer, and the current study aimed to demonstrate the profile of the CNVs for oral cavity squamous cell carcinoma (OSCC) and elucidate the clinicopathological associations and molecular mechanisms of a potential marker derived from CNVs, mixed-lineage leukemia translocated to chromosome 3 protein (MLLT3), in OSCC carcinogenesis. MATERIALS AND METHODS: CNVs in 37 OSCC tissue specimens were analyzed using a high-resolution microarray, the OncoScan array. Gene expression was analyzed by real-time polymerase chain reaction in 127 OSCC and normal tissue samples. Cell function assays included cell cycle, migration, invasion and chromatin immunoprecipitation assays. RESULTS: We found a novel copy number amplified region, chromosome 9p, encompassing MLLT3 via the comparison of our data set with six other OSCC genome-wide CNV data sets. MLLT3 overexpression was associated with poorer overall survival in patients with OSCC (p = .048). MLLT3 knockdown reduced cell migration and invasion. The reduced invasion ability in MLLT3-knockdown cells was rescued with double knockdown of MLLT3 and CBP/p300-interacting transactivator with ED rich carboxy-terminal domain 4 (CITED4; 21.0% vs. 61.5%). Knockdown of MLLT3 impaired disruptor of telomeric silencing-1-like (Dot1L)-associated hypermethylation in the promoter of the tumor suppressor, CITED4 (p < .001), and hence dysregulated HIF-1α-mediated genes (TWIST, MMP1, MMP2, VIM, and CDH1) in OSCC cells. CONCLUSION: We identified unique CNVs in tumors of Taiwanese patients with OSCC. Notably, MLLT3 overexpression is related to the poorer prognosis of patients with OSCC and is required for Dot1L-mediated transcriptional repression of CITED4, leading to dysregulation of HIF-1α-mediated genes. IMPLICATIONS FOR PRACTICE: This article reports unique copy number variations in oral cavity squamous cell carcinoma (OSCC) tumors of Taiwanese patients. Notably, MLLT3 overexpression is related to the poorer prognosis of patients with OSCC and is required for Dot1L-mediated transcriptional repression of CITED4, leading to dysregulation of HIF-1α-mediated genes.
Subject(s)
DNA Copy Number Variations , Mouth Neoplasms/genetics , Nuclear Proteins/genetics , Squamous Cell Carcinoma of Head and Neck/genetics , Cell Line, Tumor , Cell Movement/genetics , Female , Humans , Male , Middle Aged , Mouth Neoplasms/pathology , Neoplasm Invasiveness , Oligonucleotide Array Sequence Analysis , Squamous Cell Carcinoma of Head and Neck/pathology , TransfectionABSTRACT
Epidermal growth factor receptor (EGFR) and activin A are both overexpressed in oral cavity squamous cell carcinoma (OSCC). We evaluated their clinical correlation and activin A-mediated EGFR regulation in this study. Overexpression of both transcripts/proteins indicated a poorer prognosis in OSCC patients. Knockdown of endogenous INHBA repressed the expression of EGFR and inhibited activin A-mediated canonical Smads, noncanonical phosphorylation of AKT (ser473) (p-AKT ser473) and SP1. Inhibition of PI3K signaling via its inhibitor attenuated p-AKT ser473 and in turn reduced SP1 and EGFR expression in the presence of recombinant activin A (rActivin A) in OSCC cells, as revealed via a luciferase assay and western blotting. However, canonical Smad signaling repressed the EGFR promoter, as revealed by a luciferase assay. The transcription factor SP1, its coactivator CBP/p300, and Smad proteins were recruited to the EGFR proximal promoter following rActivin A treatment, as revealed by chromatin immunoprecipitation (ChIP). Smad2/3/4 dramatically outcompeted SP1 binding to the EGFR proximal promoter following mithramycin A treatment. Activin A activates the PI3K and Smad pathways to compete for binding to overlapping SP1 consensus sequences on the EGFR proximal promoter. Nevertheless, canonical p-Smad2 was largely repressed in OSCC tumor tissues, suggesting that the activin A-mediated noncanonical pathway is essential for the carcinogenesis of OSCC.
Subject(s)
Activins/metabolism , Carcinoma, Squamous Cell/genetics , ErbB Receptors/genetics , Mouth Neoplasms/genetics , Phosphatidylinositol 3-Kinases/metabolism , Promoter Regions, Genetic , Signal Transduction , Sp1 Transcription Factor/metabolism , Adult , Aged , Aged, 80 and over , Cell Movement , ErbB Receptors/metabolism , Female , Humans , Male , Middle Aged , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , RNA Interference , Smad2 Protein/metabolism , Young Adult , p300-CBP Transcription Factors/metabolismABSTRACT
Increasing evidence indicates that inflammation plays a crucial role in cancer development. A novel scoring system based on albumin and the neutrophil-to-lymphocyte ratio (NLR) was developed and incorporated into a nomogram to create a more accurate prognostic tool for oral cavity squamous cell carcinoma (OSCC) patients. A retrospective review was performed on 613 consecutive patients undergoing ablative surgery for OSCC between September 2005 and December 2014. NLR and albumin were determined and used to calculate an albumin/NLR score (ANS). The nomogram was based on the ANS and several clinicopathological manifestations, and its accuracy was determined by the concordance index (c-index). A high ANS was significantly associated with aggressive tumor behaviors, such as T status, overall stage, extranodal extension, perineural invasion, tumor depth, and decreased overall survival (OS). Multivariate analysis indicated that age, overall stage, extranodal extension, and ANS were independent factors for OS. The c-index for OS prognosis was 0.750 using this nomogram compared to 0.688 using TNM staging alone. The prognostic accuracy for OS in OSCC patients can be significantly improved using a nomogram that incorporates the novel ANS and other clinicopathological variables.
Subject(s)
Albumins/metabolism , Carcinoma, Squamous Cell/diagnosis , Carcinoma, Squamous Cell/pathology , Lymphocytes/metabolism , Mouth Neoplasms/diagnosis , Mouth Neoplasms/pathology , Neutrophils/metabolism , Nomograms , Aged , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Multivariate Analysis , PrognosisABSTRACT
BACKGROUND: The purpose of this study was to elucidate the clinicopathological associations and molecular mechanisms of karyopherin alpha 2 (KPNA2) in oral cavity squamous cell carcinoma (SCC) progression. METHODS: The KPNA2 expressions were analyzed by immunohistochemistry and enzyme-linked immunosorbent assay in 209 tissues and 181 saliva samples, respectively. The functions of KPNA2 in migration and invasion were examined in KPNA2-knowdown cells. The matrix metalloproteinase (MMP) levels were determined by real-time quantitative polymerase chain reaction (qPCR). The subcellular fraction was used to obtain the nuclear distribution of nuclear factor-kappa B (NF-κB). RESULTS: The KPNA2 overexpression was associated with extranodal extension (P < .05) and poor disease-specific survival in patients with oral cavity SCC (P < .05). The salivary KPNA2 levels were elevated in patients with oral cavity SCC (P < .05). The KPNA2 knockdown reduced cell migration and invasion. This knockdown also suppressed the interleukin (IL)-1ß-induced nuclear import of NF-κB and MMP (MMP-1, MMP-3, and MMP-9) transcription. CONCLUSION: The KPNA2 overexpression is an independent biomarker for poor prognosis of oral cavity SCC and is required for MMP-mediated metastasis.
Subject(s)
Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/mortality , Mouth Neoplasms/metabolism , Mouth Neoplasms/mortality , alpha Karyopherins/metabolism , Biomarkers, Tumor/metabolism , Carcinoma, Squamous Cell/pathology , Cell Movement , Female , Humans , Interleukin-1beta/metabolism , Male , Matrix Metalloproteinases/genetics , Matrix Metalloproteinases/metabolism , Mouth Neoplasms/pathology , NF-kappa B , Neoplasm Invasiveness , Prognosis , Real-Time Polymerase Chain Reaction , Saliva/metabolism , alpha Karyopherins/geneticsABSTRACT
Oral cavity squamous cell carcinoma (OSCC) is a leading cause of cancer-related deaths worldwide and associated with poor prognosis and mortality. Discovery of proteins that can improve OSCC treatment is needed. Using comparative proteome profiling of primary cells derived from OSCC and adjacent noncancerous epithelium, endoplasmic reticulum aminopeptidases 2 (ERAP2) has been identified as an OSCC-associated protein. Compared with the adjacent normal tissues, ERAP2 levels were determined to be significantly elevated in OSCC tissues using quantitative real-time PCR and immunohistochemistry. Importantly, overexpression of ERAP2 was associated with positive N stage, advanced overall stage, positive perineural invasion, and tumor depth (P = 0.041, 0.015, 0.010, and 0.032, respectively). The overall survival rates of patients without and with the ERAP2 overexpression were 71.9% and 56.0%, respectively (P = 0.029). Furthermore, knockdown of ERAP2 inhibited the migration and invasion abilities of OSCC cells. Our results collectively show that ERAP2 overexpression is associated with the cervical metastasis and poorer prognosis of OSCC.
ABSTRACT
The profiling of cancer cell secretomes is considered to be a good strategy for identifying cancer-related biomarkers, but few studies have focused on identifying low-molecular-mass (LMr) proteins (<15 kDa) in cancer cell secretomes. Here, we used tricine-SDS-gel-assisted fractionation and LC-MS/MS to systemically identify LMr proteins in the secretomes of five oral cavity squamous cell carcinoma (OSCC) cell lines. Cross-matching of these results with nine OSCC tissue transcriptome datasets allowed us to identify 33 LMr genes/proteins that were highly upregulated in OSCC tissues and secreted/released from OSCC cells. Immunohistochemistry and quantitative real-time PCR were used to verify the overexpression of two candidates, HMGA2 and MIF, in OSCC tissues. The overexpressions of both proteins were associated with cervical metastasis, perineural invasion, deeper tumor invasion, higher overall stage, and a poorer prognosis for post-treatment survival. Functional assays further revealed that both proteins promoted the migration and invasion of OSCC cell lines in vitro. Collectively, our data indicate that the tricine-SDS-gel/LC-MS/MS approach can be used to efficiently identify LMr proteins from OSCC cell secretomes, and suggest that HMGA2 and MIF could be potential tissue biomarkers for OSCC.