Potential Therapeutic Target For Head And Neck Squamous Cell Carcinoma Research Articles

Tumor-associated macrophage-derived exosomal miR21-5p promotes tumor angiogenesis by regulating YAP1/HIF-1α axis in head and neck squamous cell carcinoma

Extracellular vesicles (EVs) have recently received increasing attention as essential mediators of communication between tumor cells and their microenvironments. Tumor-associated macrophages (TAMs) play a proangiogenic role in various tumors, especially head and neck squamous cell carcinoma (HNSCC), and angiogenesis is closely related to tumor growth and metastasis. This research focused on exploring the mechanisms by which EVs derived from TAMs modulate tumor angiogenesis in HNSCC. Our results indicated that TAMs infiltration correlated positively with microvascular density in HNSCC. Then we collected and identified EVs from TAMs. In the microfluidic chip, TAMs derived EVs significantly enhanced the angiogenic potential of pHUVECs and successfully induced the formation of perfusable blood vessels. qPCR and immunofluorescence analyses revealed that EVs from TAMs transferred miR-21-5p to endothelial cells (ECs). And targeting miR-21-5p of TAMs could effectively inhibit TAM-EVs induced angiogenesis. Western blot and tube formation assays showed that miR-21-5p from TAM-EVs downregulated LATS1 and VHL levels but upregulated YAP1 and HIF-1α levels, and the inhibitors of YAP1 and HIF-1α could both reduce the miR-21-5p enhanced angiogenesis in HUVECs. The in vivo experiments further proved that miR-21-5p carried by TAM-EVs promoted the process of tumor angiogenesis via YAP1/HIF-1α axis in HNSCC. Conclusively, TAM-derived EVs transferred miR-21-5p to ECs to target the mRNA of LATS1 and VHL, which inhibited YAP1 phosphorylation and subsequently enhanced YAP1-mediated HIF-1α transcription and reduced VHL-mediated HIF-1α ubiquitination, contributing to angiogenesis in HNSCC. These findings present a novel regulatory mechanism of tumor angiogenesis, and miR-21-5p/YAP1/HIF-1α might be a potential therapeutic target for HNSCC.

M6A‑modified HOXC10 promotes HNSCC progression via co‑activation of ADAM17/EGFR and Wnt/β‑catenin signaling.

The homeobox (HOX) gene family plays a fundamental role in carcinogenesis. However, the oncogenic mechanism of HOXC10 in head and neck squamous cell carcinoma (HNSCC) remains unclear. In the present study, it was revealed that HOXC10 expression was significantly higher in HNSCC tissues than in adjacent tissues, and a high level of HOXC10 was closely associated with worse clinical outcomes. HOXC10 overexpression promoted HNSCC cell proliferation, migration, and invasion, both invitro and invivo. Mechanistically, chromatin immunoprecipitation sequencing revealed that HOXC10 drove the transcriptional activation of a disintegrin and metalloproteinase17 (ADAM17), and the ADAM17/epidermal growth factor receptor (EGFR)/ERK1/2 signaling pathway facilitating the proliferation of HNSCC. Furthermore, mass spectrometric analysis indicated that HOXC10 interacted with ribosomal proteinS15A (RPS15A) and enhanced RPS15A protein expression, activating the Wnt/β‑catenin pathway and contributing to invasion and metastasis of HNSCC. Additionally, the methylated RNA immune precipitation and RNA antisense purification assays showed that N6‑methyladenosine (m6A) writer, methyltransferase‑like 3, catalyzed m6A modification of the HOXC10 transcript, m6A reader insulin like growth factor2 mRNA binding protein (IGF2BP)1 and IGF2BP3 involved in recognizing and stabilizing m6A‑tagged HOXC10 mRNA. In summary, the present study identified HOXC10 as a promising candidate oncogene in HNSCC. The m6A modification‑mediated HOXC10 promoted proliferation, migration, and invasion of HNSCC through co‑activation of ADAM17/EGFR and Wnt/β‑catenin signaling, providing a novel diagnostic and prognostic biomarker and a potential therapeutic target for HNSCC.

CYP4F12 is a potential biomarker and inhibits cell migration of head and neck squamous cell carcinoma via EMT pathway

Head and neck squamous cell carcinoma (HNSC) is the most common malignant tumor of head and neck. Due to the insidious nature of HNSC and the lack of effective early diagnostic indicators, the development of novel biomarkers to improve patient prognosis is particularly urgent. In this study, we explored and validated the correlation between cytochrome P450 family 4 subfamily F member 12 (CYP4F12) expression levels and HNSC progression using data from The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO) datasets and collected patient samples. We analyzed the association of CYP4F12 expression with clinicopathological features, immune correlation and prognosis. Finally, we analyzed the correlation between CYP4F12 and pathways, and verified by experiments. The results showed that CYP4F12 was low expressed in tumor tissues, participated in a variety of phenotypic changes of HNSC and affected immune cell infiltration. Pathway analysis indicated that CYP4F12 may play a key role in tumor cell migration and apoptosis. Experimental results showed that over-expression of CYP4F12 inhibited cell migration and enhanced the adhesion between cells and matrix by inhibiting epithelial-mesenchymal transition (EMT) pathway in HNSC cells. In conclusion, our study provided insights into the role of CYP4F12 in HNSC and revealed that CYP4F12 may be a potential therapeutic target for HNSC.

Bicarbonate transporter SLC4A7 promotes EMT and metastasis of HNSCC by activating the PI3K/AKT/mTOR signaling pathway.

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. Currently, therapeutic modalities such as surgery, chemotherapy, radiotherapy, and immunotherapy are being used to treat HNSCC. However, the treatment outcomes of most patients are dismal because they are already in middle or advanced stage by the time of diagnosis and poorly responsive to treatments. It is therefore of great interest to clarify mechanisms that contribute to the metastasis of cells to identify possible targets for therapy. In this study, we identified the Na+ -coupled bicarbonate transporter, SLC4A7, play essential roles in the metastasis of HNSCC. Our results showed that the relative expression of SLC4A7 messengerRNA was highly expressed in HNSCCs samples from TCGA, and compared with precancerous cells of human oral mucosa (DOK), SLC4A7 was highly expressed in HNSCC cell lines. In vitro and in vivo experiments showed that dysregulation of SLC4A7 had minor influence on the proliferation of HNSCC but impacted HNSCC's migration and invasion. Meanwhile, SLC4A7 could promote epithelial-mesenchymal transition (EMT) in HNSCC. RNA-seq, KEGG pathway enrichment analysis and Western blot further revealed that downregulation of SLC4A7 in HNSCC cells inhibited the PI3K/AKT pathway. These findings were further validated via rescue experiments using a small molecule inhibitor of PI3K/mTOR (GDC-0980). Our findings suggest that SLC4A7 promotes EMT and metastasis of HNSCC through the PI3K/AKT/mTOR signaling pathway, which may be a valuable predictive biomarker and potential therapeutic target in HNSCC.

Survival association of XRCC1 for patients with head and neck squamous cell carcinoma: A systematic review and meta-analysis.

Background: Epidemiologic studies have demonstrated that X-ray repair cross-complementary group 1 (XRCC1) is one of the susceptibility factors in head and neck squamous cell carcinoma (HNSCC) patients. However, its clinical prognostic impact remains controversial. Thus, a meta-analysis was performed to clarify the association between XRCC1 and the survival outcomes in HNSCC patients. Methods: Following the Preferred Reporting Items or Systematic Reviews Meta Analyses (PRISMA) 2020 guidelines, literature searches were systematically performed in PubMed, EMBASE, Web of Science, Wanfang, and Chinese National Knowledge Infrastructure (CNKI) databases with manual retrieval. Hazard ratios (HRs) and 95% confidence intervals (CIs) were collected to estimate the correlation between XRCC1 and the survival outcomes of HNSCC patients. Results: Ten studies including 1995 HNSCC patients who satisfied the inclusion and exclusion criteria were included in this meta-analysis. Pooled analysis indicated that XRCC1 Arg399Gln and XRCC1 high protein expression were significantly correlated with poor overall survival with HR of 1.31 (95% CIs: 1.03-1.66, p = 0.027) and 2.32 (95% CIs: 1.55-3.48p = 0.000) in HNSCC patients. In addition, our results demonstrated that XRCC1 was significantly associated with poor progression-free survival (HR = 1.42, 95% CIs: 1.15-1.75, p = 0.001) in HNSCC patients. ConclusionThis meta-analysis demonstrated that XRCC1 Arg399Gln and XRCC1 high protein expression increase the risk of poor survival for HNSCC patients. XRCC1 is a potential therapeutic target for HNSCC.

RNA 5-Methylcytosine Regulator NSUN3 promotes tumor progression through regulating immune infiltration in head andneck squamous cell carcinoma.

This study aimed to determine whether the RNA, 5-methylcytosine (m5C), is involved in the progression of head and neck squamous cell carcinoma (HNSCC). We used least absolute shrinkage and selection operator to establish a prognostic score (PS) model based on the m5C regulator expression. Immune scores were calculated using the estimation of stromal and immune cells in malignant tumor tissues using expression data. The biological functions of the m5C regulator, NOP2/Sun RNA methyltransferase 3 (NSUN3), were thoroughly investigated in vitro and in vivo. The PS model acted as efficient prognostic factors in HNSCC. The expression of NSUN3, with the maximum weight, was found to be upregulated and indicated a poor prognosis. Meanwhile, NSUN3 knockdown inhibited the tumor proliferation and growth both in vitro and in vivo. High PS status was negatively correlated with CD8+ T, γδ+ T, and M1 macrophage percentages. NSUN3 knockdown increased the infiltration of M1 macrophages but decreased the percentage of M2 macrophages. The PS index is a novel and promising biomarker for predicting the prognosis and immune infiltration microenvironment in HNSCC. Moreover, NSUN3 plays a key role in this process and may serve as a potential therapeutic target for HNSCC.

CircRFWD3 promotes HNSCC metastasis by modulating miR-27a/b/PPARγ signaling

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer in the world, the 5-year survival rate of patients with HNSCC is still about 50% due to frequent metastasis and recurrence. Circular RNAs (circRNAs) have been characterized as key regulators of gene expression in numerous malignancies. However, the role of circRNA in HNSCC metastasis remains largely unknown. Here, we demonstrated that the circRFWD3 was significantly upregulated in HNSCC tissues and cell lines by circRNA microarray analysis and qPCR. Notably, high expression of circRFWD3 is related to highly aggressive HNSCC cell lines and lymph node metastasis in HNSCC patients. After that, Sanger sequencing, RNase R, and actinomycin D assay were performed to verify the ring structure of circRFWD3. Then functional experiments found it could promote the metastasis of HNSCC cells both in vitro and in vivo. Mechanistically, a dual-luciferase reporter assay, FISH, RIP, RNA pull-down, RNA-seq, and western blot experiments were employed and found that circRFWD3 served as a miRNAs sponge for miR-27a/27b, leading to the upregulation of PPARγ, and then promoted HNSCC metastasis via NF-κB/MMP13 pathway. Finally, ISH and IHC were carried out to determine the expression levels and clinical significances of circRFWD3 and PPARγ in clinical cohorts of HNSCC. According to the analysis results from two independent HNSCC cohorts, upregulated expression of circRFWD3 and PPARγ were positively associated with worse survival in patients with HNSCC. Overall, our results uncover that circRFWD3 acts a critical role in promoting the aggressiveness of HNSCC cells and is a prognostic marker for the disease, indicating that circRFWD3 may act as a potential therapeutic target in HNSCC.

SPDEF suppresses head and neck squamous cell carcinoma progression by transcriptionally activating NR4A1

SAM pointed domain containing E26 transformation-specific transcription factor (SPDEF) plays dual roles in the initiation and development of human malignancies. However, the biological role of SPDEF in head and neck squamous cell carcinoma (HNSCC) remains unclear. In this study, the expression level of SPDEF and its correlation with the clinical parameters of patients with HNSCC were determined using TCGA-HNSC, GSE65858, and our own clinical cohorts. CCK8, colony formation, cell cycle analysis, and a xenograft tumor growth model were used to determine the molecular functions of SPDEF in HNSCC. ChIP-qPCR, dual luciferase reporter assay, and rescue experiments were conducted to explore the potential molecular mechanism of SPDEF in HNSCC. Compared with normal epithelial tissues, SPDEF was significantly downregulated in HNSCC tissues. Patients with HNSCC with low SPDEF mRNA levels exhibited poor clinical outcomes. Restoring SPDEF inhibited HNSCC cell viability and colony formation and induced G0/G1 cell cycle arrest, while silencing SPDEF promoted cell proliferation in vitro. The xenograft tumor growth model showed that tumors with SPDEF overexpression had slower growth rates, smaller volumes, and lower weights. SPDEF could directly bind to the promoter region of NR4A1 and promoted its transcription, inducing the suppression of AKT, MAPK, and NF-κB signaling pathways. Moreover, silencing NR4A1 blocked the suppressive effect of SPDEF in HNSCC cells. Here, we demonstrate that SPDEF acts as a tumor suppressor by transcriptionally activating NR4A1 in HNSCC. Our findings provide novel insights into the molecular mechanism of SPDEF in tumorigenesis and a novel potential therapeutic target for HNSCC.

The role of SPP1 as a prognostic biomarker and therapeutic target in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is one of the most common malignancies and has a low 5-year survival rate. Mounting evidence suggests that oral potentially malignant disorders, such as oral leukoplakia (OLK), may progress to HNSCC. Given that OLK and HNSCC are often insidious and asymptomatic, the identification of markers of OLK malignant transformation and therapeutic targets in HNSCC is critical. Using various online tools and publicly available gene expression datasets, the secreted phosphoprotein 1 gene (SPP1) was identified as a significant differentially expressed gene among OLK, HNSCC, and non-cancerous tissues. SPP1 mRNA levels were elevated in HNSCC tissues and were associated with cancer stage, tumor grade, and human papillomavirus infection status. High SPP1 mRNA levels were correlated with poor overall survival of HNSCC patients. In contrast, SPP1 mutations were not significantly associated with overall survival, although their frequency in HNSCC was very low (0.6%). Furthermore, SPP1 expression levels in HNSCC were positively correlated with the infiltration of CD4+ cells, macrophages, neutrophils, and dendritic cells. The study results suggest that SPP1 may represent a diagnostic and prognostic biomarker, as well as a potential therapeutic target in HNSCC.

HOXB7 acts as an oncogenic biomarker in head and neck squamous cell carcinoma

BackgroundThe homeobox gene Homeobox B7 (HOXB7) is overexpressed across a range of cancers and promotes tumorigenesis through varying effects on proliferation, survival, migration and invasion. However, its expression pattern and oncogenic role of HOXB7 in head and neck squamous cell carcinoma (HNSCC) remain largely unexplored. Here, we aimed to explore the expression pattern of HOXB7, its clinical significance as well as functional roles in HNSCC.MethodsHOXB7 mRNA expression in HNSCC was determined by data mining and analyses from TCGA (The Cancer Genome Atlas) and GEO (Gene Expression Omnibus) datasets. The protein abundance of HOXB7 was measured by immunohistochemistry in 119 primary HNSCC samples and associations between its expression and clinicopathological parameters and patient survival were evaluated. The pro-tumorigenic roles of HOXB7 in HNSCC were further delineated in vitro by loss-of-function assay. And a xenograft tumor model was established in nude mice to assess the role of HOXB7 in tumor growth. Connectivity Map (CMap) analysis was performed to identify bioactive small molecules which might be potential inhibitors for HOXB7.ResultsBioinformatics analyses showed that HOXB7 mRNA was significantly overexpressed in 8 independent HNSCC datasets from TCGA and GEO databases. HOXB7 protein was markedly upregulated in HNSCC samples as compared to normal counterparts and its overexpression significantly associated with high pathological grade, advanced clinical stage, cervical node metastasis (P = 0.0195, 0.0152, 0.0300) and reduced overall and disease-free survival (P = 0.0014, 0.0007). Univariate and multivariate Cox regression analyses further revealed HOXB7 as an independent prognostic factor for patients’ overall survival. Moreover, HOXB7 knockdown significantly inhibited cell proliferation, migration and invasion and induced cell apoptosis in HNSCC cells, and resulted in compromised tumour growth in vivo. Furthermore, CMap (Connectivity map) analysis has identified three potential bioactive small molecule inhibitors (NU-1025, thiamine, vinburnine) for HOXB7 targeted therapy in HNSCC.ConclusionsOur findings revealed that overexpression of HOXB7 was associates with tumour aggressiveness and unfavourable prognosis by serving a novel prognostic biomarker in HNSCC. Moreover, HOXB7 might be involved in the development and progression of HNSCC as an oncogene, and thereby might be a potential therapeutic target for HNSCC.

Lactate secreted by PKM2 upregulation promotes Galectin-9-mediated immunosuppression via inhibiting NF-\u03baB pathway in HNSCC

Pyruvate kinase M2 as a key rate-limiting enzyme in glycolysis, it plays a critical role in metabolic reprogramming and carcinogenesis. However, whether PKM2 can promote immunosuppressive microenvironment formation remains unknown in head and neck squamous cell carcinoma (HNSCC). PKM2 expression was detected using immunohistochemical staining. The biological functions of PKM2 were investigated in vitro and in vivo. Lactate production and the expression of Galectin-9, a critical immunosuppression molecule, were detected after PKM2 knockdown and overexpression in HNSCC cells. The mechanism of lactate regulating Galectin-9 expression through NF-κB signaling was explored in vitro. Overexpression of PKM2 correlates with poor prognosis in HNSCC patients. Silencing PKM2 markedly inhibits proliferation and metastasis capacity in vivo and in vitro, and vice versa. The glycolysis and glycolytic capacity are significantly decreased after PKM2 silencing. Lactate secretion induced by PKM2 significantly promotes migration and invasion capacity. Furthermore, a positive correlation between PKM2 and Galectin-9 expression is observed in HNSCC tissues. The induction of Galectin-9 expression by PKM2 can be affected by a lactate transporter inhibitor. Mechanically, lactate impeded the suppressive transcriptional complex formation of NF-κB and histone deacetylase 3 (HDAC3), which released the transcription of Galectin-9 mediated by NF-κB signaling. Our findings demonstrate that lactate produced by PKM2 upregulation promotes tumor progression and Galectin-9-mediated immunosuppression via NF-κB signaling inhibition in HNSCC, which bridges metabolism and immunosuppression. The novel PKM2-lactate-Galectin-9 axis might be a potential therapeutic target in HNSCC.

DNAJA1 promotes cancer metastasis through interaction with mutant p53.

Accumulation of mutant p53 (mutp53) is crucial for its oncogenic gain of function activity. DNAJA1, a member of J-domain containing proteins or heat shock protein 40, is shown to prevent unfolded mutp53 from proteasomal degradation. However, the biological function of DNAJA1 remains largely unknown. Here we show that DNAJA1 promotes tumor metastasis by accumulating unfolded mutp53. Levels of DNAJA1 in head and neck squamous cell carcinoma (HNSCC) tissues were higher than those in normal tissues. Knockdown of DNAJA1 in HNSCC cell lines carrying unfolded mutp53 significantly decreased the levels of mutp53, filopodia/lamellipodia formation, migratory potential, and active forms of CDC42/RAC1, which were not observed in HNSCC cells with DNA contact mutp53, wild-type p53, or p53 null. Such mutp53-dependent functions of DNAJA1 were supported by the observation that DNAJA1 selectively bound to unfolded mutp53. Moreover, DNAJA1 knockdown in HNSCC cells carrying unfolded mutp53 inhibited primary tumor growth and metastases to the lymph nodes and lungs. Our study suggests that DNAJA1 promotes HNSCC metastasis mainly in a manner dependent on mutp53 status, suggesting DNAJA1 as a potential therapeutic target for HNSCC harboring unfolded mutp53.

MTDH in macrophages promotes the vasculogenic mimicry via VEGFA-165/Flt-1 signaling pathway in head and neck squamous cell carcinoma

Vasculogenic mimicry (VM) refers to vessel-like structures formed by aggressive tumor cells and is closely associated with cancer invasion and metastasis. Here, we investigated the effect of macrophage-derived MTDH on VM formation in head and neck squamous cell carcinoma (HNSCC) and its underlying mechanism. Macrophages with MTDH overexpression (Mac-MTDH) promoted cancer cell VM formation, migration, and invasion in vitro. Moreover, MTDH overexpression triggered macrophage polarization into M2 type tumor-associated macrophages. Analysis of HNSCC clinical samples revealed that MTDH+ macrophages were predominantly located in the tumor-stromal region in proximity to VM and correlated with lymph node metastasis. Mechanistically, Mac-MTDH enhanced the expression and secretion of VEGFA-165 rather than other VEGFA isoforms via ß-catenin. The VEGFA-165/Flt-1 axis was responsible for Mac-MTDH’s effects in cancer cells through p-STAT3/Twist1/VE-cadherin pathway. Using mouse model, we further confirmed that Mac-MTDH increased VM formation and cancer metastasis in vivo. Furthermore, in subcutaneous xenograft mouse model, HN6 + Mac-MTDH tumor exhibited elevated expression of p-STAT3 and Twist1 than HN6 + Mac-NC tumors. This study revealed that Mac-MTDH promoted VM formation, cancer cell migration and invasion, and cancer metastasis through VEGFA-165/Flt-1 axis, and that macrophage-derived MTDH could be a potential therapeutic target in HNSCC.

The prognostic significance of survivin expression in patients with HNSCC: a systematic review and meta-analysis

BackgroundSurvivin has been recently identified as a promising novel therapeutic target and prognostic marker in different types of cancer. Here we conducted a comprehensive meta-analysis to better clarify they the precise prognostic and diagnostic value of survivin in head and neck squamous cell carcinoma (HNSCC).MethodsDatabase of PubMed (Medline), Embase, and Web of Science were systematically searched for related published literature up to September 2020. Pooled hazards ratios (HR) and related 95% confidence intervals (CI) were used to estimate the association of survivin expression and survival outcomes in HNSCC patients.ResultsTwenty eight studies with 4891 patients were finally included in this meta-analysis, the pooled analysis indicated that the survivin expression was significantly correlated with poorer overall survival (OS) (HR, 2.02; 95% CI, 1.65–2.47, P < 0.001), and poorer disease-free survival (DFS)/ disease-specific survival (DSS) (HR = 2.03, 95%CI: 1.64–2.52, P < 0.001; HR = 1.92, 95%CI: 1.41–2.60, P < 0.001, receptively). Similar results were observed in subgroup analysis stratified by different cancer types, such as laryngeal squamous cell carcinoma (LSCC) (HR = 1.35, 95%CI: 1.05–1.74, P < 0.001), oral squamous cell carcinomas (OSCC) (HR = 2.45, 95%CI: 1.89–3.17, P < 0.001), nasopharyngeal carcinoma (NPC) (HR = 2.53, 95%CI: 1.76–3.62, P < 0.001) and HNSCC (HR = 1.52, 95%CI: 1.25–1.86, P < 0.001). Furthermore, ethnicity-stratified analysis indicated that survivin was significantly associated with poorer OS among both Asian and Non- Asian HNSCC patients (HR = 2.16, 95%CI: 1.76–2.66; HR = 1.56, 95%CI: 1.33–1.82, respectively).ConclusionsOur results suggested that survivin is predictors of worse prognosis in HNSCC patients. Hence, survivin is a potential therapeutic target for HNSCC.

RUNX1 promotes MAPK signaling to increase tumor progression and metastasis via OPN in head and neck cancer.

Tumor progression and metastasis are still major burdens for head and neck squamous cell carcinoma (HNSCC). Runt-related transcription factor 1 (RUNX1) is involved in aggressive phenotypes in several cancers, while the molecular role of RUNX1 underlying cancer progression and metastasis of HNSCC remains largely unknown. In our study, RUNX1 expression was increased with disease progression in patients with HNSCC. The silencing of RUNX1 significantly decelerated the malignant progression of HNSCC cells, reduced osteopontin (OPN) expression in vitro and weakened the tumorigenicity of HNSCC cells in vivo. Moreover, we demonstrated that RUNX1 activated the mitogen-activated protein kinase signaling by directly binding to the promoter of OPN in tumor progression and metastasis of HNSCC. Our results may provide new insight into the mechanisms underlying the role of RUNX1 in tumor progression and metastasis and reveal the potential therapeutic target in HNSCC.

The interaction of interleukin-8 and PTEN inactivation promotes the malignant progression of head and neck squamous cell carcinoma via the STAT3 pathway

Interleukin-8 (IL-8) expression correlates with poor prognosis in many cancers, including head and neck squamous cell carcinoma (HNSCC), but the underlying mechanism is poorly understood. In this study, we found that overexpression of IL-8 correlated with poor outcome in HNSCC patients. IL-8 significantly increased cellular proliferation, migration, and invasion ability both in vitro and in vivo, which could be blocked by a CXCR1/2 inhibitor. IL-8 promoted the expression of MMP2, MMP9, snail, and vimentin in HNSCC cells. Furthermore, IL-8 could inactivate PTEN via phosphorylation, and then inactivated PTEN affected the phosphorylation of STAT3. Recombinant PTEN that internalized in cytoplasm decreased the expression of phosphorylated STAT3, while knockdown of PTEN led to the increased expression of phosphorylated STAT3. A STAT3 inhibitor could reverse the upregulation of invasion-associated proteins mediated by IL-8 stimulation. Furthermore, overexpression of snail and inactivated PTEN jointly promoted the autocrine effect of IL-8 on tumor cells. Last, there were positive correlations between IL-8 and snail, vimentin expression in HNSCC tissues. In summary, our study demonstrates that PTEN acts as a novel “molecular switch” to regulate IL-8/STAT3 signaling, promoting the progression of HNSCC, and indicating that this pathway may be a potential therapeutic target for HNSCC.

Long Noncoding RNA LINC00460 Promotes Cell Progression by Sponging miR-4443 in Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinoma (HNSCC) is one of the most common cancers worldwide. Long noncoding RNAs were proved to be associated with the development and progression in HNSCC. However, the mechanism of LINC00460 in HNSCC needs to be further investigated. The study used quantitative real-time polymerase chain reaction assay to detect the expression of LINC00460 in cancer tissues and cell lines. Gain and loss of function experiments were conducted to analyze the effects of LINC00460 and miR-4443 on cell proliferation, invasion, and apoptosis of HNSCC cells in vitro. The interactions among miR-4443 and LINC00460 were detected by dual-luciferase reporter assay. Here, the study showed that LINC00460 was highly expressed in HNSCC tissues and cell lines. Functionally, knockdown of LINC00460 inhibited HNSCC cell proliferation and migration in vitro. Besides, LINC00460 promoted cell progression by sponging miR-4443, and miR-4443 inhibitor could reverse the effects of si-LINC00460 on cell proliferation and migration. In summary, LINC00460 could potentially promote cell progression and epithelial mesenchymal transition by sponging miR-4443 in HNSCC. LINC00460 could be used as a potential therapeutic target for HNSCCs.

Knockdown of LINC01116 inhibits cell migration and invasion in head and neck squamous cell carcinoma through epithelial-mesenchymal transition pathway.

Long noncoding RNAs (lncRNAs) are linked to tumor development and progression. The aim of this study was to determine the prognostic significance and biological role of LINC01116 in head and neck squamous cell carcinoma (HNSCC). We identified 21 aberrantly expressed lncRNAs specific to HNSCC that were common in two microarray datasets. LINC01116 was highly overexpressed in HNSCC tissues and was correlated to shorter overall survival and relapse-free survival duration, as analyzed by the online Gene Expression Profiling Interactive Analysis platform. LINC01116 was also overexpressed in oral squamous cell carcinoma and nasopharyngeal carcinoma tissues, and LINC01116 silencing significantly inhibited the migration and invasion capacities of both cell lines by blocking the epithelial-mesenchymal transition process. In addition, 125 coexpressing genes were identified by circlncRNAnet, and were mainly located on human autosomes and enriched in transforming growth factor-β signaling pathway. These findings indicate that LINC01116 might be a potential therapeutic target for HNSCC.

NOVA1 induction by inflammation and NOVA1 suppression by epigenetic regulation in head and neck squamous cell carcinoma

Neuro-oncological ventral antigen 1 (NOVA1) is known as a neuron-specific pre-mRNA binding splicing factor. Previously, it was shown to be highly upregulated in T lymphocytes, as well as fibroblasts/stromal spindle cells, in tertiary lymphoid tissues formed by the benign immune-inflammatory process, while it was frequently downregulated in tumor cells and other cells within the tumor microenvironment. Here, we sought to identify the mechanisms of NOVA1 modulation in head and neck squamous cell carcinoma (HNSCC). NOVA1 was induced by inflammatory-immune signals within the tumor microenvironment and was suppressed by epigenetic dysregulation, such as that with miR-146. We found attenuated expression of NOVA1 to be associated with non-oropharynx sites such as oral cavity, hypopharynx, and larynx, human papilloma virus (HPV)-negative SCC defined by immunohistochemistry for p16INK4a expression, fewer tumor infiltrating lymphocytes, and poor patient outcomes. Moreover, changes were discovered in epithelial mesenchymal transition-associated markers according to NOVA1 status. This study provides some insights to the underlying mechanism of NOVA1 regulation and suggests that NOVA1 may serve as a prognostic biomarker and potential therapeutic target for HNSCC in the future.

CD100-plexin-B1 induces epithelial-mesenchymal transition of head and neck squamous cell carcinoma and promotes metastasis.

Head and neck squamous cell carcinoma (HNSCC) is one of the most lethal cancers mainly due to the high rate of metastasis. Here, we find that the expression level of CD100 in HNSCC is positively correlated with the T category, pathological grade and lymph node metastasis of the tumor. The level of soluble CD100 (sCD100) is highly increased in serum of HNSCC patients, and sCD100 markedly induces the epithelial-mesenchymal transition (EMT) of HNSCC through its receptor, Plexin-B1 (PlxnB1), and promotes the metastasis in a xenograft mouse model. Furthermore, sCD100 promotes the stabilization of Snail through the regulation of the Vav1-Rac1/RhoA-p21-activated kinase pathway for the induction of EMT. Anti-CD100 antibody abolishes the CD100-induced EMT and prevents the metastasis of HNSCC, and anti-CD100 antibody also increases the drug sensitivity of HNSCC. Taken together, our study shows for the first time that CD100 induces the EMT of HNSCC and promotes the metastasis, and CD100 would be a candidate as a novel prognostic biomarker and a potential therapeutic target for HNSCC.