EGFR-PKM2 signaling promotes the metastatic potential of nasopharyngeal carcinoma through induction of FOSL1 and ANTXR2

Silencing AHNAK promotes nasopharyngeal carcinoma progression by upregulating the ANXA2 protein

PURPOSE

Nasopharyngeal carcinoma (NPC) is an aggressive head and neck disease with a high incidence of distant metastases. Enlargeosomes are cytoplasmic organelles marked by, desmoyokin/AHNAK. This study aimed to evaluate the expression of AHNAK in NPC and its effect on enlargeosomes and to investigate the correlation between AHNAK expression levels and clinical NPC patient characteristics.

METHODS

Primary nasopharyngeal carcinoma (NPC) and NPC specimens were evaluated by analyzing public data, and immunohistochemistry. Systematic in vitro and in vivo experiments were performed using different NPC-derived cell lines and mouse models.

RESULTS

In this study, we detected AHNAK and Annexin A2(ANXA2), a protein coating the surface of enlargeosomes, in NPC samples. We found that AHNAK was down-regulated. Down-regulation of AHNAK was associated with poor overall survival in NPC patients. Moreover, transcription factor FOSL1-mediated transcriptional repression was responsible for the low expression of AHNAK by recruiting EZH2. Whereas Annexin A2 was upregulated in human NPC tissues. Upregulation of Annexin A2 was associated with lymph node metastasis and distant metastasis in NPC patients. Functional studies confirmed that silencing of AHNAK enhanced the growth, invasion, and metastatic properties of NPC cells both in vitro and in vivo. In terms of mechanism, loss of AHNAK led to an increase of annexin A2 protein level in NPC cells. Silencing ANXA2 restored NPC cells' migrative and invasive ability upon loss of AHNAK.

CONCLUSION

Here, we report AHNAK as a tumor suppressor in NPC, which may act through annexin A2 oncogenic signaling in enlargeosome, with potential implications for novel approaches to NPC treatment.

The enzymes of serine synthesis pathway in cancer metastasis

Metastasis, the major cause of cancer mortality, requires cancer cells to reprogram their metabolism to adapt to and thrive in different environments, thereby leaving metastatic cells metabolic characteristics different from their parental cells. Mounting research has revealed that the de novo serine synthesis pathway (SSP), a glycolytic branching pathway that consumes glucose carbons for serine makeup and α-ketoglutarate generation and thus supports the proliferation, survival, and motility of cancer cells, is one such reprogrammed metabolic pathway. During different metastatic cascades, the SSP enzyme proteins or their enzymatic activity are both dynamically altered; manipulating their expression or catalytic activity could effectively prevent the progression of cancer metastasis; and the SSP enzymatic proteins could even conduce to metastasis via their nonenzymatic functions. In this article we overview the SSP dynamics during cancer metastasis and put the focuses on the regulatory role of the SSP in metastasis and the underlying mechanisms that mainly involve cellular anabolism/catabolism, redox balance, and epigenetics, aiming to provide a theoretical basis for the development of therapeutic strategies for targeting metastatic lesions.

Role of RNA binding proteins of the Drosophila behavior and human splicing (DBHS) family in health and cancer

RNA-binding proteins (RBPs) play crucial roles in the functions and homoeostasis of various tissues by regulating multiple events of RNA processing including RNA splicing, intracellular RNA transport, and mRNA translation. The Drosophila behavior and human splicing (DBHS) family proteins including PSF/SFPQ, NONO, and PSPC1 are ubiquitously expressed RBPs that contribute to the physiology of several tissues. In mammals, DBHS proteins have been reported to contribute to neurological diseases and play crucial roles in cancers, such as prostate, breast, and liver cancers, by regulating cancer-specific gene expression. Notably, in recent years, multiple small molecules targeting DBHS family proteins have been developed for application as cancer therapeutics. This review provides a recent overview of the functions of DBHS family in physiology and pathophysiology, and discusses the application of DBHS family proteins as promising diagnostic and therapeutic targets for cancers.

Metabolic reprogramming in nasopharyngeal carcinoma: Mechanisms and therapeutic opportunities

The high prevalence of metabolic reprogramming in nasopharyngeal carcinoma (NPC) offers an abundance of potential therapeutic targets. This review delves into the distinct mechanisms underlying metabolic reprogramming in NPC, including enhanced glycolysis, nucleotide synthesis, and lipid metabolism. All of these changes are modulated by Epstein-Barr virus (EBV) infection, hypoxia, and tumor microenvironment. We highlight the role of metabolic reprogramming in the development of NPC resistance to standard therapies, which represents a challenging barrier in treating this malignancy. Furthermore, we dissect the state of the art in therapeutic strategies that target these metabolic changes, evaluating the successes and failures of clinical trials and the strategies to tackle resistance mechanisms. By providing a comprehensive overview of the current knowledge and future directions in this field, this review sets the stage for new therapeutic avenues in NPC.

Super Enhancer Driven Hyaluronan Synthase 3 Promotes Malignant Progression of Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is a malignant tumor of the head and neck with high metastatic and invasive nature. Super enhancers (SEs) control the expression of cell identity genes and oncogenes during tumorigenesis. As a glycosaminoglycan in the tumor microenvironment, hyaluronan (HA) is associated with cancer development. High expression of hyaluronan synthase 3 (HAS3) resulted in HA deposition, which promoted the growth of cancer cell. However, its role in NPC development remains elusive. We demonstrated that the levels of HAS3 mRNA or protein were increased in NPC cell lines. Transcription of HAS3 is associated with SE. Disruption of SE by bromodomain containing 4 (BRD4) inhibitor JQ1 resulted in downregulation of HAS3 and inhibition of cell proliferation and invasiveness in NPC cells. Inhibition of HA synthesis by HAS inhibitor 4-MU suppressed cell growth and invasion of NPC cells, whereas HA treatment exerted opposite effects. Genetically silencing HAS3 in HK1 and FaDu NPC cells attenuated cell proliferation and mobility, while re-expression of HAS3 enhanced malignant potential of CNE1 and CNE2 NPC cells. Furthermore, loss of HAS3 impaired metastatic potential of HK1 cells in nude mice. Mechanistically, inhibition of HA synthesis by chemical inhibitor or silencing HAS3 led to reduction of the levels of phosphorylation of EGFR, AKT, and ERK proteins. In contrast, exogenous HA treatment or forced expression of HAS3 activated EGFR/AKT/ERK signaling cascade. This study suggested that HAS3 is driven by SE and overexpressed in NPC. High expression of HAS3 promotes the malignant features of NPC via activation of EGFR/AKT/ERK signaling pathway.

Single-cell RNA sequencing reveals cellular and molecular reprograming landscape of gliomas and lung cancer brain metastases

BACKGROUND

Brain malignancies encompass gliomas and brain metastases originating from extracranial tumours including lung cancer. Approximately 50% of patients with lung adenocarcinoma (LUAD) will eventually develop brain metastases. However, the specific characteristics of gliomas and lung-to-brain metastases (LC) are largely unknown.

METHODS

We applied single-cell RNA sequencing to profile immune and nonimmune cells in 4 glioma and 10 LC samples.

RESULTS

Our analysis revealed that tumour microenvironment (TME) cells are present in heterogeneous subpopulations. LC reprogramed cells into immune suppressed state, including microglia, macrophages, endothelial cells, and CD8⁺ T cells, with unique cell proportions and gene signatures. Particularly, we identified that a subset of macrophages was associated with poor prognosis. ROS (reactive oxygen species)-producing neutrophils was found to participant in angiogenesis. Furthermore, endothelial cells participated in active communication with fibroblasts. Metastatic epithelial cells exhibited high heterogeneity in chromosomal instability (CIN) and cell population.

CONCLUSIONS

Our findings provide a comprehensive understanding of the heterogenicity of the tumor microenvironment and tumour cells and it will be crucial for successful immunotherapy development for brain metastasis of lung cancer.

The role of altered microRNA expression in premalignant and malignant head and neck lesions with epithelial origin

Background and Aims

The premalignant lesions of the oral cavity carry a risk of transformation to malignancy. Hence, early diagnosis followed by timely intervention remarkably affects the prognosis of patients. During tumorigenesis, particular microRNAs (miRNAs) show altered expressions and because of their post transcriptionally regulatory role could provide favorable diagnostic, therapeutic, or prognostic values in head and neck cancers.

Methods

In this review, we have demonstrated diagnostic, prognostic, and potential therapeutic roles of some miRNAs associated with oral premalignant and malignant lesions based on previous validate studies.

Results

It is previously documented that dysregulation of miRNAs contributes to cancer development and progression. MiRNAs could be tumor suppressors that normally suppress cell proliferation, differentiation, and apoptosis or play as oncogenes that improved tumorigenesis process. Altered expression of miRNAs has also been reported in premalignant oral epithelial lesions such as leukoplakia, oral submucous fibrosis, oral lichen planus and some malignant carcinoma like oral squamous cell, verrucous, spindle cell, Merkel cell carcinoma and basal cell.

Conclusion

Some of miRNAs could be new therapeutic candidates in miRNA‐based target gene therapy. Although more investigations are required to identify the most favorable miRNA candidate, altered expression of some miRNAs could be used as biomarkers in premalignant lesions and oral cancers with high sensitivity and specificity.

lncRNA NEAT1 promotes the proliferation and metastasis of hepatocellular carcinoma by regulating the FOXP3/PKM2 axis

Objective

Hepatocellular carcinoma (HCC) is a malignant tumor. The occurrence of HCC is involved in the alteration of a variety of oncogenes or tumor suppressor genes, but the specific molecular mechanism remains unknown. This research proved the effects of long non-coding RNA NEAT1 (lncRNA NEAT1) on the viability, proliferation, migration, and invasion of hepatocellular carcinoma cells and explored the mechanism behind these effects.

Methods

NEAT1 in 97H and Huh7 cell lines was overexpressed or knocked down, respectively. The expression of FOXP3 and its target gene PKM2 was hinged on qRT-PCR and Western blot, respectively. RNA pulldown and RNA immunoprecipitation experiments were carried out to detect the interaction between NEAT1 and proteins. Finally, the effect of NEAT1 on the tumor volume of HCC was verified by animal experiments.

Results

A series of experiments have shown that NEAT1 knockdown can inhibit the viability, proliferation, migration, and invasion of HCC cells; NEAT1 can bind FOXP3 to promote PKM2 transcription; PKM2 knockdown can inhibit the viability, proliferation, migration, and invasion of HCC cells; and PKM2 knockdown reversed the function of NEAT1.

Conclusion

lncRNA NEAT1 can promote the malignant behavior of HCC cells, while silencing of NEAT1 can inhibit that behavior of HCC cells. Mechanically, NEAT1 promotes the transcriptional activation of PKM2 by binding FOXP3, and PKM2 knockout reverses the function of NEAT1.

Proteomic profiling of plasma exosomes reveals CD82 involvement in the development of esophageal squamous cell carcinoma

The Xinjiang Uygur autonomous region has a high incidence of esophageal cancer. For the early diagnosis of patients with esophageal squamous cell carcinoma (ESCC), exosomes were isolated and quantified by liquid chromatography tandem mass spectrometry ((LC-MS/MS) with data independent acquisition (DIA) from the peripheral blood of patients with benign esophageal disease (BED), esophageal intraepithelial neoplasia (EIN) and ESCC. A total of 1117 proteins were identified in the above 9 samples. The proteomic results showed that the quantity of CD82 in exosomes of EIN was significantly higher than that in patients with BED and ESCC. Meanwhile, our ELISA test verified our proteomic results. In addition, the immunohistochemical results showed high CD82 expression in adjacent normal tissues and low expression in ESCC tissues. CD82 expression in ESCC tissues was negatively correlated with tumor stage and the expression of PKM2, and the high expression of CD82 combined with low expression of PKM2 in ESCC tissues suggested a good prognosis. To further clarify the tumor suppressive mechanism of CD82, the TIMER and TISDB databases were analyzed, and CD82 expression in tumor tissues was found to be related to the infiltration of immune cells. CD82 in exosomes is involved in the development of ESCC. SIGNIFICANCE: Xinjiang is a high incidence area of ESCC. When diagnosed in the middle and late stages of the disease, the prognosis of patients is poor. Exosomes provide the possibility of relatively noninvasive and early detection of esophageal carcinogenesis. To the best of our knowledge, this was the first study using the DIA technique to analyze the exosomal proteins of patients with different stages of ESCC. The proteins identified in the exosomes in these three groups could provide insights for understanding how exosomes promote the occurrence of ESCC, the antitumour mechanism of humans and the early diagnosis of ESCC.

Chemo-Immunotherapy Regimes for Recurrent or Metastatic Nasopharyngeal Carcinoma: A Network Meta-Analysis and Cost-Effectiveness Analysis

Introduction: In 2021, two phase III clinical trials confirmed that toripalimab or camrelizumab combined with gemcitabine and cisplatin (TGP or CGP) provide more benefits in the first-line treatment of R/M NPC than GP. Fortunately, TGP and CGP were recently approved as first-line treatments for cases experiencing R/M NPC by the China National Medical Products Administration in 2021. However, due to the high cost and variety of treatment options, the promotion of chemo-immunotherapeutics in the treatment of R/M NPC remains controversial. Therefore, we performed a cost-effectiveness assessment of the two newly approved treatment strategies to assess which treatments provide the greatest clinical benefits at a reasonable cost.

Methods: A cost-effectiveness analysis and network meta-analysis network meta-analysis was conducted based on the JUPITER-02 and CAPTAIN-first Phase 3 randomized clinical trials. A Markov model was expanded for the evaluation of the effectiveness and cost of TGP, CGP, and GP chemotherapy with a 10-years horizon and measured the health achievements in quality-adjusted life-years (QALYs), incremental cost-effectiveness ratios (ICERs), and life-years (LYs). We constructed a treatment strategy and other parameters based on two clinical trials and performed one-way and probabilistic sensitivity experiments for the evaluation of the uncertainty in the model.

Results: For the model of patients with treatment-R/M NPC, TGP was associated with a total cost of $48,525 and 2.778 QALYs (4.991 LYs), leading to an ICER of $15,103 per QALY ($10,321 per LY) compared to CGP. On comparing the GP chemotherapy, we found TGP and CGP incurred substantial health costs, resulting in ICERs of $19,726 per QALY and $20,438 per QALY, respectively. The risk of adverse events (AEs) and the price of the drugs had significant impacts on the ICER. At the assumed willingness-to-pay (WTP) threshold of $35,673 per QALY, there were approximately 75.8 and 68.5% simulations in which cost-effectiveness was achieved for TGP and CGP, respectively.

Conclusion: From the Chinese payer’s perspective, TGP is more possible to be a cost-effective regimen compared with CGP and GP for first-line treatment of patients with R/M NPC at a WTP threshold of $35,673 per QALY.

CircCRIM1 promotes nasopharyngeal carcinoma progression via the miR-34c-5p/FOSL1 axis

BACKGROUND

Nasopharyngeal carcinoma (NPC) is a rare malignancy with multiple risk factors (Epstein-Barr virus, etc.) that seriously threatens the health of people. CircRNAs are known to regulate the tumorigenesis of malignant tumours, including NPC. Moreover, circCRIM1 expression is reported to be upregulated in NPC. Nevertheless, the impact of circCRIM1 on NPC progression is not clear.

METHODS

An MTT assay was performed to assess cell viability. In addition, cell invasion and migration were assessed by the transwell assay. Dual luciferase assays were performed to assess the association among circCRIM1, miR-34c-5p and FOSL1. Moreover, RT-qPCR was applied to assess mRNA levels, and protein levels were determined by Western blot.

RESULTS

CircCRIM1 and FOSL1 were upregulated in NPC cells, while miR-34c-5p was downregulated. Knockdown of circCRIM1 significantly decreased the invasion, viability and migration of NPC cells. The miR-34c-5p inhibitor notably promoted the malignant behaviour of NPC cells, while miR-34c-5p mimics exerted the opposite effect. Moreover, circCRIM1 could bind with miR-34c-5p, and FOSL1 was identified to be downstream of miR-34c-5p. Furthermore, circCRIM1 downregulation notably inhibited the proliferation and invasion of NPC cells, while this phenomenon was significantly reversed by FOSL1 overexpression.

CONCLUSION

Silencing circCRIM1 inhibited the tumorigenesis of NPC. Thus, circCRIM1 might be a novel target for NPC.

Genetic susceptibility to patient-reported xerostomia among long-term oropharyngeal cancer survivors

Genetic susceptibility for xerostomia, a common sequela of radiotherapy and chemoradiotherapy for head and neck cancer, is unknown. Therefore, to identify genetic variants associated with moderate to severe xerostomia, we conducted a GWAS of 359 long-term oropharyngeal cancer (OPC) survivors using 579,956 autosomal SNPs. Patient-reported cancer treatment-related xerostomia was assessed using the MD Anderson Symptom Inventory. Patient response was dichotomized as moderate to severe or none to mild symptoms. In our study, 39.2% of OPC survivors reported moderate to severe xerostomia. Our GWAS identified eight SNPs suggestively associated with higher risk of moderate to severe xerostomia in six genomic regions (2p13.3, rs6546481, Minor Allele (MA) = A, ANTXR1, P = 4.3 × 10-7; 5p13.2-p13.1, rs16903936, MA = G, EGFLAM, P = 5.1 × 10-6; 4q21.1, rs10518156, MA = G, SHROOM3, P = 7.1 × 10-6; 19q13.42, rs11882068, MA = G, NLRP9, P = 1.7 × 10-5; 12q24.33, rs4760542, MA = G, GLT1D1, P = 1.8 × 10-5; and 3q27.3, rs11714564, MA = G, RTP1, P = 2.9 × 10-5. Seven SNPs were associated with lower risk of moderate to severe xerostomia, of which only one mapped to specific genomic region (15q21.3, rs4776140, MA = G, LOC105370826, a ncRNA class RNA gene, P = 1.5 × 10-5). Although our small exploratory study did not reach genome-wide statistical significance, our study provides, for the first time, preliminary evidence of genetic susceptibility to xerostomia. Further studies are needed to elucidate the role of genetic susceptibility to xerostomia.

Investigation of the potential of bile acid methyl esters as inhibitors of aldo-keto reductase 1C2: insight from molecular docking, virtual screening, experimental assays and molecular dynamics

Human aldo-keto reductase 1C isoforms catalyze reduction of endogenous and exogenous compounds, including therapeutic drugs, and are associated with chemotherapy resistance. AKR1C2 is involved in metastatic processes and is a target for the treatment of various cancers. Here we used molecular docking to explore a series of bile acid methyl esters as AKR1C2 inhibitors. Autodock 4.2 ranked 10 of 11 test compounds above decoys based on ursodeoxycholate, an AKR1C2 inhibitor, while 5 ranked above 94% of decoys in Autodock Vina. Seven inactives reported not to inhibit AKR1C2 ranked below the decoy threshold. Virtual screen of a natural product library in Autodock Vina using the same parameters, identified steroidal derivatives, bile acids, and other AKR1C ligands in the top 5%. In experiments, 6 out of 11 tested bile acid methyl esters inhibited >50% of AKR1C2 activity, while 2 compounds were AKR1C3 inhibitors. The top ranking compound showed dose-dependent inhibition of AKR1C2 (IC50 ~3.6 µM). Molecular dynamics was used to explore interactions between a bile acid methyl ester and the AKR1C2 active site. Our molecular docking results identify AKR1C2 as a target for bile acid methyl esters, which combined with virtual screening results provides new directions for the synthesis of AKR1C inhibitors.

The Fra-1/AP-1 Oncoprotein: From the "Undruggable" Transcription Factor to Therapeutic Targeting

The genetic and epigenetic changes affecting transcription factors, coactivators, and chromatin modifiers are key determinants of the hallmarks of cancer. The acquired dependence on oncogenic transcriptional regulators, representing a major determinant of cancer cell vulnerability, points to transcription factors as ideal therapeutic targets. However, given the unavailability of catalytic activities or binding pockets for small-molecule inhibitors, transcription factors are generally regarded as undruggable proteins. Among components of the AP-1 complex, the FOS-family transcription factor Fra-1, encoded by FOSL1, has emerged as a prominent therapeutic target. Fra-1 is overexpressed in most solid tumors, in response to the BRAF-MAPK, Wnt-beta-catenin, Hippo-YAP, IL-6-Stat3, and other major oncogenic pathways. In vitro functional analyses, validated in onco-mouse models and corroborated by prognostic correlations, show that Fra-1-containing dimers control tumor growth and disease progression. Fra-1 participates in key mechanisms of cancer cell invasion, Epithelial-to-Mesenchymal Transition, and metastatic spreading, by driving the expression of EMT-inducing transcription factors, cytokines, and microRNAs. Here we survey various strategies aimed at inhibiting tumor growth, metastatic dissemination, and drug resistance by interfering with Fra-1 expression, stability, and transcriptional activity. We summarize several tools aimed at the design and tumor-specific delivery of Fra-1/AP-1-specific drugs. Along with RNA-based therapeutics targeting the FOSL1 gene, its mRNA, or cognate regulatory circRNAs, we will examine the exploitation of blocking peptides, small molecule inhibitors, and innovative Fra-1 protein degraders. We also consider the possible caveats concerning Fra-1 inhibition in specific therapeutic contexts. Finally, we discuss a recent suicide gene therapy-based approach, aimed at selectively killing the Fra-1-overexpressing neoplastic cells.

Advances in pathogenesis and precision medicine for nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a squamous carcinoma with apparent geographical and racial distribution, mostly prevalent in East and Southeast Asia, particularly concentrated in southern China. The epidemiological trend over the past decades has suggested a substantial reduction in the incidence rate and mortality rate due to NPC. These results may reflect changes in lifestyle and environment, and more importantly, a deeper comprehension of the pathogenic mechanism of NPC, leading to much progress in the preventing, screening, and treating for this cancer. Herein, we present the recent advances on the key signal pathways involved in pathogenesis of NPC, the mechanism of Epstein‐Barr virus (EBV) entry into the cell, and the progress of EBV vaccine and screening biomarkers. We will also discuss in depth the development of various therapeutic approaches including radiotherapy, chemotherapy, surgery, targeted therapy, and immunotherapy. These research advancements have led to a new era of precision medicine in NPC.

Exploration of a Novel Prognostic Risk Signature and Its Effect on the Immune Response in Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is a highly invasive and metastatic carcinoma with different molecular characteristics and clinical outcomes. In this work, we aimed to establish a novel gene signature that could predict the prognosis of NPC patients. A total of 13 significant genes between the recurrence/metastasis (RM) group and the no recurrence/metastasis (no-RM) group were identified by machine learning from RNA-Seq data including 60 NPC tumor biopsies. Based on these genes, a 4-mRNA signature (considering U2AF1L5, TMEM265, GLB1L and MLF1) was identified. Receiver operating characteristic (ROC) and Kaplan-Meier (K-M) analyses indicated that this signature had good prognostic value for NPC. The overall survival (OS) and progression-free survival (PFS) of the patients in the high-risk group were significantly shorter than those of the patients in the low-risk group (p = 0.00126 and p = 0.000059, respectively). The area under the ROC curve (AUC) values of the 4-mRNA signature were higher than those of T stage and N stage for OS (0.893 vs 0.619 and 0.582, respectively) and PFS (0.86 vs 0.538 and 0.622, respectively). Furthermore, the 4-mRNA signature was closely associated with cell proliferation and the immune response. The expression of GLB1L and TMEM265 was associated with the level of tumor-infiltrating immune cells (r > 0.4, p < 0.05). We have validated the model through measuring the expression levels of the 4-mRNA signature by qRT-PCR, in an independent cohort of NPC patients. Here, we report a novel gene signature that can serve as a new tool for predicting the prognosis of NPC patients.

Role of PKM2-Mediated Immunometabolic Reprogramming on Development of Cytokine Storm

The cytokine storm is a marker of severity of various diseases and increased mortality. The altered metabolic profile and energy generation of immune cells affects their activation, exacerbating the cytokine storm. Currently, the emerging field of immunometabolism has highlighted the importance of specific metabolic pathways in immune regulation. The glycolytic enzyme pyruvate kinase M2 (PKM2) is a key regulator of immunometabolism and bridges metabolic and inflammatory dysfunction. This enzyme changes its conformation thus walks in different fields including metabolism and inflammation and associates with various transcription factors. This review summarizes the vital role of PKM2 in mediating immunometabolic reprogramming and its role in inducing cytokine storm, with a focus on providing references for further understanding of its pathological functions and for proposing new targets for the treatment of related diseases.

Metabolic Reprogramming and Immune Evasion in Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is a malignant tumor of the nasopharynx mainly characterized by geographic distribution and EBV infection. Metabolic reprogramming, one of the cancer hallmarks, has been frequently reported in NPCs to adapt to internal energy demands and external environmental pressures. Inevitably, the metabolic reprogramming within the tumor cell will lead to a decreased pH value and diverse nutritional supplements in the tumor-infiltrating micro-environment incorporating immune cells, fibroblasts, and endothelial cells. Accumulated evidence indicates that metabolic reprogramming derived from NPC cells may facilitate cancer progression and immunosuppression by cell-cell communications with their surrounding immune cells. This review presents the dysregulated metabolism processes, including glucose, fatty acid, amino acid, nucleotide metabolism, and their mutual interactions in NPC. Moreover, the potential connections between reprogrammed metabolism, tumor immunity, and associated therapy would be discussed in this review. Accordingly, the development of targets on the interactions between metabolic reprogramming and immune cells may provide assistances to overcome the current treatment resistance in NPC patients.

Targeting pyruvate kinase muscle isoform 2 (PKM2) in cancer: What do we know so far?

Cancer is a leading cause of death globally. Cancer cell transformation is the result of intricate crosstalk between intracellular components and proteins. A characteristic feature of cancer cells is the ability to reprogram their metabolic pathways to ensure their infinite proliferative potential. Pyruvate kinase muscle isoform 2 (PKM2) is a glycolytic enzyme that plays crucial roles in cancer, apart from carrying out its metabolic roles. PKM2 is involved in all the major events associated with cancer growth. Modulation of PKM2 activity (dimer inhibition or tetramer activation) has been successful in controlling cancer. However, recent studies provide contrary evidences regarding the oncogenic functions of PKM2. Moreover, several studies have highlighted the cancerous roles of PKM1 isoform in certain contexts. The present review aims at providing the current updates regarding PKM2 targeting in cancer. Further, the review discusses the contradictory results that suggest that both the isoforms of PKM can lead to cancer growth. In conclusion, the review emphasizes revisiting the approaches to target cancer metabolism through PKM to find novel and effective targets for anticancer therapy.

Nasopharyngeal Carcinoma: The Role of the EGFR in Epstein-Barr Virus Infection

Epstein-Barr virus (EBV), a type 4 γ herpes virus, is recognized as a causative agent in nasopharyngeal carcinoma (NPC). Incidence of EBV-positive NPC have grown in recent decades along with worse outcomes compared with their EBV-negative counterparts. Latent membrane protein 1 (LMP1), encoded by EBV, induces NPC progression. The epidermal growth factor receptor (EGFR), a member of the ErbB family of receptor tyrosine kinases (RTK), is a driver of tumorigenesis, including for NPC. Little data exist on the relationship between EGFR and EBV-induced NPC. In our initial review, we found that LMP1 promoted the expression of EGFR in NPC in two main ways: the NF-κB pathway and STAT3 activation. On the other hand, EGFR also enhances EBV infection in NPC cells. Moreover, activation of EGFR signalling affects NPC cell proliferation, cell cycle progression, angiogenesis, invasion, and metastasis. Since EGFR promotes tumorigenesis and progression by downstream signalling pathways, causing poor outcomes in NPC patients, EGFR-targeted drugs could be considered a newly developed anti-tumor drug. Here, we summarize the major studies on EBV, EGFR, and LMP1-regulatory EGFR expression and nucleus location in NPC and discuss the clinical efficacy of EGFR-targeted agents in locally advanced NPC (LA NPC) and recurrent or metastatic NPC (R/M NPC) patients.

Nuclear Pyruvate Kinase M2 (PKM2) Contributes to Phosphoserine Aminotransferase 1 (PSAT1)-Mediated Cell Migration in EGFR-Activated Lung Cancer Cells

Simple Summary

Alternative functions for metabolic proteins have recently been shown to drive cancer growth. These may include differential enzymatic activity or novel protein associations. Phosphoserine aminotransferase 1 (PSAT1) participates in cellular serine synthesis and has been observed to be elevated in different tumor types. In this study, we aimed to identify new putative PSAT1 activities and determine their contribution to lung tumor progression. We found a direct association for PSAT1 with another enzyme, pyruvate kinase M2. While this appears not to affect PKM2’s metabolic activity, PSAT1 is required for the specific cellular localization of PKM2 upon tumorigenic signaling. Further, the depletion of PSAT1 suppresses lung cancer cell movement that can be partially restored by the compartment expression of PKM2. These findings reveal a novel mechanism that is able to promote the spread of this deadly disease.

Abstract

An elevated expression of phosphoserine aminotransferase 1 (PSAT1) has been observed in multiple tumor types and is associated with poorer clinical outcomes. Although PSAT1 is postulated to promote tumor growth through its enzymatic function within the serine synthesis pathway (SSP), its role in cancer progression has not been fully characterized. Here, we explore a putative non-canonical function of PSAT1 that contributes to lung tumor progression. Biochemical studies found that PSAT1 selectively interacts with pyruvate kinase M2 (PKM2). Amino acid mutations within a PKM2-unique region significantly reduced this interaction. While PSAT1 loss had no effect on cellular pyruvate kinase activity and PKM2 expression in non-small-cell lung cancer (NSCLC) cells, fractionation studies demonstrated that the silencing of PSAT1 in epidermal growth factor receptor (EGFR)-mutant PC9 or EGF-stimulated A549 cells decreased PKM2 nuclear translocation. Further, PSAT1 suppression abrogated cell migration in these two cell types whereas PSAT1 restoration or overexpression induced cell migration along with an elevated nuclear PKM2 expression. Lastly, the nuclear re-expression of the acetyl-mimetic mutant of PKM2 (K433Q), but not the wild-type, partially restored cell migration in PSAT1-silenced cells. Therefore, we conclude that, in response to EGFR activation, PSAT1 contributes to lung cancer cell migration, in part, by promoting nuclear PKM2 translocation.

Current Status and Future Perspectives about Molecular Biomarkers of Nasopharyngeal Carcinoma

Simple Summary

Nasopharyngeal carcinoma is a serious major public health problem in its endemic countries. Up to 80% of NPC patients with locally advanced disease or distant metastasis at diagnosis were associated with poor prognosis and with median survival less than 4 months. The mortality rate of NPC metastasis is up to 91%. To date, there is no available curative treatment or reliable early diagnosis or prognosis for NPC. Discovery and development of reliable early diagnosis and prognosis biomarkers for nasopharyngeal carcinoma are urgent needed. Hence, we have here listed the potential early diagnosis and prognosis biomarker candidates for nasopharyngeal carcinoma. This review will give an insight to readers on the progress of NPC biomarker discovery to date, as well as future prospective biomarker development and their translation to clinical use.

Abstract

Nasopharyngeal carcinoma (NPC) is an epithelial malignancy that shows a remarkable ethnic and geographical distribution. It is one of the major public health problems in some countries, especially Southern China and Southeast Asia, but rare in most Western countries. Multifactorial interactions such as Epstein–Barr virus infection, individual’s genetic susceptibility, as well as environmental and dietary factors may facilitate the pathogenesis of this malignancy. Late presentation and the complex nature of the disease have led it to become a major cause of mortality. Therefore, an effective, sensitive, and specific molecular biomarker is urgently needed for early disease diagnosis, prognosis, and prediction of metastasis and recurrence after treatment. In this review, we discuss the recent research status of potential biomarker discovery and the problems that need to be explored further for better NPC management. By studying the aberrant pattern of these candidate biomarkers that promote NPC development and progression, we are able to understand the complexity of this malignancy better, hence positing our stands better towards strategies that may provide a way forward to the discovery of more reliable and specific biomarkers for diagnosis and targeted therapeutic development.

Natural product triptolide induces GSDME-mediated pyroptosis in head and neck cancer through suppressing mitochondrial hexokinase-ΙΙ

Background

Pyroptosis is a lytic cell death form executed by gasdermins family proteins. Induction of tumor pyroptosis promotes anti-tumor immunity and is a potential cancer treatment strategy. Triptolide (TPL) is a natural product isolated from the traditional Chinese herb which possesses potent anti-tumor activity in human cancers. However, its role in pyroptosis remains to be elucidated.

Methods

Cell survival was measured by colony formation assay. Cell apoptosis was determined by Annexin V assay. Pyroptosis was evaluated by morphological features and release of interleukin 1β and lactate dehydrogenase A (LDHA). Immunofluorescence staining was employed to measure subcellular localization of proteins. Tumorigenicity was assessed by a xenograft tumor model. Expression levels of mRNAs or proteins were determined by qPCR or western blot assay, respectively.

Results

Triptolide eliminates head and neck cancer cells through inducing gasdermin E (GSDME) mediated pyroptosis. Silencing GSDME attenuates the cytotoxicity of TPL against cancer cells. TPL treatment suppresses expression of c-myc and mitochondrial hexokinase II (HK-II) in cancer cells, leading to activation of the BAD/BAX-caspase 3 cascade and cleavage of GSDME by active caspase 3. Silencing HK-II sensitizes cancer cells to TPL induced pyroptosis, whereas enforced expression of HK-II prevents TPL induced pyroptosis. Mechanistically, HK-II prevents mitochondrial translocation of BAD, BAX proteins and activation of caspase 3, thus attenuating cleavage of GSDME and pyroptosis upon TPL treatment. Furthermore, TPL treatment suppresses NRF2/SLC7A11 (also known as xCT) axis and induces reactive oxygen species (ROS) accumulation, regardless of the status of GSDME. Combination of TPL with erastin, an inhibitor of SLC7A11, exerts robust synergistic effect in suppression of tumor survival in vitro and in a nude mice model.

Conclusions

This study not only provides a new paradigm of TPL in cancer therapy, but also highlights a crucial role of mitochondrial HK-II in linking glucose metabolism with pyroptosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-01995-7.

What are the applications of single-cell RNA sequencing in cancer research: a systematic review

Single-cell RNA sequencing (scRNA-seq) is a tool for studying gene expression at the single-cell level that has been widely used due to its unprecedented high resolution. In the present review, we outline the preparation process and sequencing platforms for the scRNA-seq analysis of solid tumor specimens and discuss the main steps and methods used during data analysis, including quality control, batch-effect correction, normalization, cell cycle phase assignment, clustering, cell trajectory and pseudo-time reconstruction, differential expression analysis and gene set enrichment analysis, as well as gene regulatory network inference. Traditional bulk RNA sequencing does not address the heterogeneity within and between tumors, and since the development of the first scRNA-seq technique, this approach has been widely used in cancer research to better understand cancer cell biology and pathogenetic mechanisms. ScRNA-seq has been of great significance for the development of targeted therapy and immunotherapy. In the second part of this review, we focus on the application of scRNA-seq in solid tumors, and summarize the findings and achievements in tumor research afforded by its use. ScRNA-seq holds promise for improving our understanding of the molecular characteristics of cancer, and potentially contributing to improved diagnosis, prognosis, and therapeutics.

RNA-binding protein YBX1 promotes cell proliferation and invasiveness of nasopharyngeal carcinoma cells via binding to AURKA mRNA

Background: RNA-binding proteins (RBPs) play essential roles in post-transcriptional control of gene expression. Dysregulation of RBPs is intensively implicated in development and progression of human diseases, including cancers. However, the roles of RBPs in nasopharyngeal carcinoma (NPC), which is a distinct subtype of head and neck cancer, remain elusive. Methods: NPC-related RBPs were explored by analyzing GEO database and high-throughput proteomic data obtained from crosslinking immunoprecipitation. The expression levels of Y box binding protein 1 (YBX1) protein in NPC samples were measured by immunohistochemistry (IHC) staining. The association of YBX1 protein levels with prognosis of NPC patients was analyzed by Kaplan-Meier Plotter. The expression levels of YBX1 in NPC cells were inhibited by RNA interference. Cell growth was measured by CCK-8 assay. Cell mobility and invasiveness were measured by transwell assays. Tumorigenicity was measured by using a xenograft tumor assay. The expression levels of mRNAs or proteins were determined by qPCR or western blot assays, respectively. The mRNAs binding to YBX1 were determined by RNA immunoprecipitation (RIP) and qPCR. The effect of YBX1 on mRNA translation was measured by luciferase reporter assay. Results: In the present study, we demonstrated a differentially expressed RBPs profile between NPC and its normal counterpart. Among these aberrantly expressed RBPs, YBX1 was overexpressed in NPC. We found that YBX1 is mainly localized in the cytoplasm of NPC cells. Loss of YBX1 led to reduced cell proliferation, migration and invasiveness in vitro, and reduced tumorigenicity in vivo. Overexpression of YBX1 associates with high expression of cell cycle G2/M checkpoint modulators. In addition, YBX1 promotes AURKA protein expression by directly binding to its mRNA. Loss of YBX1 leads to reduction of AURKA protein level. Forced expression of AURKA rescues cell proliferation and invasiveness in YBX1-silenced NPC cell. Conclusions: The current study indicated that YBX1 promotes NPC cell proliferation and invasiveness through enhancing protein synthesis of AURKA.

Mechanisms of vasculogenic mimicry in hypoxic tumor microenvironments

Background

Vasculogenic mimicry (VM) is a recently discovered angiogenetic process found in many malignant tumors, and is different from the traditional angiogenetic process involving vascular endothelium. It involves the formation of microvascular channels composed of tumor cells; therefore, VM is considered a new model for the formation of new blood vessels in aggressive tumors, and can provide blood supply for tumor growth. Many studies have pointed out that in recent years, some clinical treatments against angiogenesis have not been satisfactory possibly due to the activation of VM. Although the mechanisms underlying VM have not been fully elucidated, increasing research on the soil “microenvironment” for tumor growth suggests that the initial hypoxic environment in solid tumors is inseparable from VM.

Main body

In this review, we describe that the stemness and differentiation potential of cancer stem cells are enhanced under hypoxic microenvironments, through hypoxia-induced epithelial-endothelial transition (EET) and extracellular matrix (ECM) remodeling to form the specific mechanism of vasculogenic mimicry; we also summarized some of the current drugs targeting VM through these processes, suggesting a new reference for the clinical treatment of tumor angiogenesis.

Conclusion

Overall, the use of VM inhibitors in combination with conventional anti-angiogenesis treatments is a promising strategy for improving the effectiveness of targeted angiogenesis treatments; further, considering the importance of hypoxia in tumor invasion and metastasis, drugs targeting the hypoxia signaling pathway seem to achieve good results.

CYFRA21-1/TG ratio as an accurate risk factor to predict eye metastasis in nasopharyngeal carcinoma: A STROBE-compliant article

Nasopharyngeal carcinoma (NPC) has a distinctive geographical distribution in China, especially southern China. There are several risk factors for NPC, such as Epstein-Barr virus, genetics, and environmental exposures. Although the incidence of eye metastasis (EM) is lower than metastasis in other body parts, it often indicates poor prognosis.We assessed several serum biomarkers for their ability to predict EM in NPC. Patients with NPC were selected (n = 963), and were separated into two groups, EM and no eye metastasis. Ten factors were analyzed in both groups including triglyceride (TG), high-density lipoprotein, low-density lipoprotein, alkaline phosphatase, alpha fetoprotein, carbohydrate antigen-199, cancer antigen-153, apolipoproteins AI, apolipoprotein B, and cytokeratin fragment 19 (CYFRA21-1). Independent t tests, binary logistic regression, and receiver operating characteristic curves were used to assess the data.The EM group had significantly higher CYFRA21-1 and lower TG compared with the no eye metastasis group. Areas under the curve for CYFRA21-1, TG and CYFRA21-1/TG were 0.966, 0.771, and 0.976, respectively. The corresponding cut-off values were 12.12 ng/ml, 0.41 mmol/L, and 13.5. The sensitivity and specificity of CYFRA21-1/TG were 100% and 92.2%, respectively.The increased ratio of CYFRA21-1 to TG can be an accurate method to detect EM in patients with NPC.

TP63 links chromatin remodeling and enhancer reprogramming to epidermal differentiation and squamous cell carcinoma development

Squamous cell carcinoma (SCC) is an aggressive malignancy that can originate from various organs. TP63 is a master regulator that plays an essential role in epidermal differentiation. It is also a lineage-dependent oncogene in SCC. ΔNp63α is the prominent isoform of TP63 expressed in epidermal cells and SCC, and overexpression promotes SCC development through a variety of mechanisms. Recently, ΔNp63α was highlighted to act as an epidermal-specific pioneer factor that binds closed chromatin and enhances chromatin accessibility at epidermal enhancers. ΔNp63α coordinates chromatin-remodeling enzymes to orchestrate the tissue-specific enhancer landscape and three-dimensional high-order architecture of chromatin. Moreover, ΔNp63α establishes squamous-like enhancer landscapes to drive oncogenic target expression during SCC development. Importantly, ΔNp63α acts as an upstream regulator of super enhancers to activate a number of oncogenic transcripts linked to poor prognosis in SCC. Mechanistically, ΔNp63α activates genes transcription through physically interacting with a number of epigenetic modulators to establish enhancers and enhance chromatin accessibility. In contrast, ΔNp63α also represses gene transcription via interacting with repressive epigenetic regulators. ΔNp63α expression is regulated at multiple levels, including transcriptional, post-transcriptional, and post-translational levels. In this review, we summarize recent advances of p63 in epigenomic and transcriptional control, as well as the mechanistic regulation of p63.

Treatment of Recurrent or Metastatic Nasopharyngeal Carcinoma by Targeting the Epidermal Growth Factor Receptor Combined with Gemcitabine Plus Platinum

Purpose

The purpose of this study was to evaluate the anti-tumor activity and safety of anti-epidermal growth factor receptor (EGFR) monoclonal antibody combined with gemcitabine plus platinum (GP) as a first-line treatment for recurrent or metastatic nasopharyngeal carcinoma (RM-NPC).

Patients and Methods

This retrospective study analyzed RM-NPC patients at Sun Yat-sen University Cancer Center who received anti-EGFR antibody plus GP as a first-line treatment between July 2007 and November 2018. Survival analyses were performed using the Kaplan–Meier method with Log rank test. Cox proportional hazards model was used for the multivariate analysis.

Results

A total of 84 patients were enrolled. The median progression-free survival (PFS) was 10.3 months (95% CI, 6.9–13.6 months), and the median overall survival (OS) was 42.8 months (95% CI, 24.6–60.9 months). The objective response rate and disease control rate were 67.9% and 92.9%, respectively. The multivariate analysis identified a higher baseline EBV DNA level as a risk factor for both PFS (P=0.025) and OS (P=0.013). Additionally, age≥44 years (P =0.003), non-cisplatin (P= 0.009), and poor KPS (≤80) (P =0.034) were other risk factors for OS. The most common adverse events were leukopenia (n=73, 86.9%). The most common grade 3–4 AEs were leukopenia (n=30, 35.7%) and thrombocytopenia (n=22, 26.2%).

Conclusion

Anti-EGFR monoclonal antibody plus GP achieved promising antitumor activity with a tolerable toxicity profile in RM-NPC as a first-line treatment. Randomized clinical trials are warranted to compare the efficacy of GP with or without anti-EGFR antibody in these patients.

Metastatic Patterns and Prognosis of de novo Metastatic Nasopharyngeal Carcinoma in the United States

OBJECTIVE

To evaluate the distant metastatic patterns and prognostic factors for overall survival (OS) and cancer-specific survival (CSS) in de novo metastatic nasopharyngeal carcinoma (mNPC) using the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Patients with de novo mNPC who had been diagnosed between 2004 and 2016 were identified from the SEER database. Kaplan-Meier analysis was used to calculate OS and CSS. Log-rank tests were employed to measure survival variation among subgroups. Individual predictors of CSS and OS were examined using Cox proportional-hazards regression models in patients with de novo mNPC.

RESULTS

We evaluated 224 patients with de novo mNPC who matched our inclusion criteria. Three-year CSS and OS for the whole cohort was 29.8% and 27.9%, respectively. Univariate analysis indicated that CSS and OS were influenced by age, histology, radiotherapy, chemotherapy, and liver metastasis. Neither the number of metastatic sites nor their specific location in bone, lungs, distant lymph nodes or brain significantly affected CSS or OS. The aforementioned independent prognosticators continued to significantly influence survival following multivariate analysis. Taking distant metastasis without liver involvement as a reference, liver metastasis was associated significantly with shorter OS at a hazard ratio (HR) of 1.581 (P = .021) and CSS at a HR of 1.643 (P = .016). Older age, keratinizing squamous cell carcinoma, no chemotherapy, and no radiotherapy were also prognosticators for poor OS (P < .05). Similar results were documented for CSS (P < .05).

CONCLUSION

For patients with de novo mNPC, liver metastasis is an independent prognosticator for inferior CSS and OS.

LEVEL OF EVIDENCE

3a Laryngoscope, 131:E1130-E1138, 2021.

LncRNA AATBC regulates Pinin to promote metastasis in nasopharyngeal carcinoma

Long noncoding RNA (lncRNA) have emerged as crucial regulators for a myriad of biological processes, and perturbations in their cellular expression levels have often been associated with cancer pathogenesis. In this study, we identified AATBC (apoptosis‐associated transcript in bladder cancer, LOC284837) as a novel lncRNA. AATBC was found to be highly expressed in nasopharyngeal carcinoma (NPC), and increased AATBC expression was associated with poor survival in patients with NPC. Furthermore, AATBC promoted migration and invasion of NPC cells in vitro, as well as metastasis in vivo. AATBC upregulated the expression of the desmosome‐associated protein pinin (PNN) through miR‐1237‐3p sponging. In turn, PNN interacted with the epithelial–mesenchymal transition (EMT) activator ZEB1 and upregulated ZEB1 expression to promote EMT in NPC cells. Collectively, our results indicate that AATBC promotes NPC progression through the miR‐1237‐3p–PNN–ZEB1 axis. Our findings indicate AATBC as a potential prognostic biomarker or therapeutic target in NPC.

FOXA1 Suppresses the Growth, Migration, and Invasion of Nasopharyngeal Carcinoma Cells through Repressing miR-100-5p and miR-125b-5p

Background: Nasopharyngeal carcinoma (NPC) is a unique subtype of head and neck cancer, within highest incidence in South China and southeastern Asia but rare in other regions worldwide. FOXA1 is a pioneer factor implicated in various human malignancies. Downregulation of FOXA1 promotes NPC cells proliferation, invasiveness in vitro and tumorigenicity in vivo. However, it is remain elusive to determine whether microRNAs (miRNAs) regulated by FOXA1 contribute to NPC progression.

Methods: In this study, differentially expressed miRNAs and mRNAs induced by FOXA1 expression were determined by microarray. Integrative miRNA-mRNA regulatory networks mediated by FOXA1 in NPC were established. The expressions of differentially expressed miRNAs in NPC cells were measured by quantitative reverse-transcription PCR. Cell viability was determined by CCK-8 assays. Cell migration and invasiveness were measured by Transwell assays. The correlation between miRNAs and its target mRNAs was analyzed.

Results: FOXA1 suppressed the expression of miR-100-5p and miR-125b-5p in NPC cells. Silencing either miR-100-5p or miR-125b-5p inhibited the malignant behaviors of NPC cells, whereas re-expression of miR-100-5p or miR-125b-5p restored the malignancy of NPC cells repressed by FOXA1. Mechanistically, miR-100-5p or miR-125b-5p suppressed RASGRP3 or FOXN3 expression respectively via direct binding to its 3'-UTR. Furthermore, we demonstrated that FOXA1 induced RASGRP3 or FOXN3 expression via inhibiting miR-100-5p or miR-125b-5p. Upregulation of RASGRP3 or FOXN3 contributed to inhibition of NPC by FOXA1. We also demonstrated that the mRNA levels of RASGRP3 and FOXN3 are positively correlated with FOXA1.

Conclusion: Our study provided evidence the first time that FOXA1 suppresses NPC cells via downregulation of miR-100-5p or miR-125b-5p.