Bilateral squamous cell carcinoma of the temporal bone:A report of two cases and a systematic review of the literature

Objective:two new cases of temporal bone squamous cell carcinoma(TBSCC)with a bilateral occurrence are presented.Furthermore,a review of the literature was performed and the yearly incidence was calculated.Methods:A systematic review of the literature was conducted using PRISMA guidelines.Results:Twenty-two more cases were found in literature.With a total of 24 cases,the calculated yearly incidence of bilateral TBSCC is 49:10^12 A history of chronic otitis or regional radiotherapy was found in respectively 50%and 12%of patients.In nine patients,the tumors developed synchronously(within 6 months)and in 13 metachronously.Conclusions:The calculated incidence is 89 times higher than mathematically expected considering the incidence of unilateral cases.An explanation might be a history of chronic otitis or prior radiotherapy.The tumor staging of both the first tumor group and the contralateral tumor group are similar to unilateral temporal bone squamous cell carcinoma series.

Primary parenchymal squamous cell carcinoma of the kidney:A case report

BACKGROUND Primary squamous cell carcinoma(SCC)of the renal parenchyma is extremely rare,with only nine cases reported.CASE SUMMARY This study reports a 51-year-old man with primary SCC of the renal parenchyma.The patient was admitted with recurrent dull pain and discomfort in the right lumbar region,which had worsened over 2 weeks,accompanied by painful gross hematuria.SCC antigen(SCCA)levels were elevated,and imaging revealed a renal mass with associated calculi.The patient underwent laparoscopic unilateral nephrectomy and lymph node dissection.Postoperative pathology confirmed highly differentiated SCC with necrosis in the right renal parenchyma,with negative renal pelvis and ureter.The pathological stage was Pt3aN1M0.Four months after surgery,the tumor recurred with involvement of the liver,right psoas major muscle,and inferior vena cava.The patient refused chemotherapy and succumbed to the disease 6 months postoperatively due to disease progression.CONCLUSION We report a case of primary SCC of the renal parenchyma,a rare renal malignancy.The clinical symptoms,laboratory tests,and imaging findings are nonspecific,making accurate and timely diagnosis challenging.According to the literature,for patients with renal calculi accompanied by a renal mass,elevated serum SCCA levels,and magnetic resonance imaging showing cystic or cystic-solid masses within the kidney with pseudocapsules and heterogeneous mild enhancement,the possibility of this disease should be considered.

Activin A receptor type 1C single nucleotide polymorphisms associated with esophageal squamous cell carcinoma risk in Chinese population

BACKGROUND Transforming growth factor-β(TGF-β)superfamily plays an important role in tumor progression and metastasis.Activin A receptor type 1C(ACVR1C)is a TGF-βtype I receptor that is involved in tumorigenesis through binding to dif-ferent ligands.AIM To evaluate the correlation between single nucleotide polymorphisms(SNPs)of ACVR1C and susceptibility to esophageal squamous cell carcinoma(ESCC)in Chinese Han population.METHODS In this hospital-based cohort study,1043 ESCC patients and 1143 healthy controls were enrolled.Five SNPs(rs4664229,rs4556933,rs77886248,rs77263459,rs6734630)of ACVR1C were assessed by the ligation detection reaction method.Hardy-Weinberg equilibrium test,genetic model analysis,stratified analysis,linkage disequi-librium test,and haplotype analysis were conducted.RESULTS Participants carrying ACVR1C rs4556933 GA mutant had significantly decreased risk of ESCC,and those with rs77886248 TA mutant were related with higher risk,especially in older male smokers.In the haplotype analysis,ACVR1C Trs4664229Ars4556933Trs77886248Crs77263459Ars6734630 increased risk of ESCC,while Trs4664229Grs4556933Trs77886248Crs77263459Ars6734630 was associated with lower susceptibility to ESCC.CONCLUSION ACVR1C rs4556933 and rs77886248 SNPs were associated with the susceptibility to ESCC,which could provide a potential target for early diagnosis and treatment of ESCC in Chinese Han population.

Residual gastric cancer with a mixed small cell neuroendocrine and keratinizing squamous cell carcinoma:A case report

BACKGROUND Despite advancements in early detection and treatment,the prognosis and his-tological types for residual gastric cancer(GC)remains poor.CASE SUMMARY This case report presents a rare occurrence of residual GC featuring a combination of small cell neuroendocrine carcinoma(SCNEC)and squamous cell carcinoma(SCC)in a 60-year-old male patient.The patient,with a history of Billroth II gas-trectomy for duodenal ulcer bleeding,presented with gastrointestinal bleeding.Preoperative computed tomography and positron emission tomography-compu-ted tomography indicated adenocarcinoma with tumor and abdominal lymph node metastasis.The patient underwent laparoscopic total gastrectomy and ly-mph node dissection for residual GC.Histological examination of the resected tumor confirmed the presence of both SCNEC and SCC.Postoperatively,the patient underwent adjuvant chemotherapy four times.Two years later,the patient was found to occur esophageal cancer and was performed a small bowel stoma and radical esophagectomy.CONCLUSION In this case report,we detail a rare instance of residual GC with mixed SCNEC and SCC,emphasizing the complexity of diagnosis and treatment,and the need for ongoing research.

Identifying adipocyte-derived exosomal miRNAs as potential novel prognostic markers for radiotherapy of esophageal squamous cell carcinoma

BACKGROUND Radiation resistance limits radiotherapy efficacy in esophageal squamous cell carcinoma(ESCC).The tumor microenvironment,particularly adipocytes,plays a role in promoting cancer progression.Extracellular vesicles and microRNAs(miRNAs)regulate gene expression and hold prognostic potential for esophageal carcinoma.Elucidating radioresistance mechanisms and identifying radiosensitization targets can help enhance radiotherapy efficacy for esophageal cancer.AIM To investigate the potential role of miRNAs derived from adipocyte exosomes as prognostic markers for radiotherapy efficacy in ESCC.METHODS Free adipocytes were isolated from human thoracic adipose tissue.A co-culture model of adipocytes and ESCC cells was established to observe colony formation and cell survival post-irradiation.ESCC cell apoptosis was assessed by flow cytometry.Western Blot and immunofluorescence assays were performed to evaluate DNA damage in ESCC cells post-irradiation.Adipocyte-derived exosomes were isolated by ultracentrifugation and identified by electron microscopy.A similar set of experiments was performed on ESCC cells to analyze cell survival,apoptosis,and DNA damage post-radiation exposure.Exosomes from adipose tissue and serum exosomes from ESCC patients pre-and post-radiotherapy were subjected to high-throughput miRNA-sequencing and validated using real-time quantitative polymerase chain reaction.The correlation between potential target miRNAs and the short-term prognosis of radiotherapy in ESCC was evaluated by receiver operating characteristic curve analysis.RESULTS Co-culturing adipocytes with ESCC cells enhanced radioresistance,as evidenced by increased colony formation.Adipocyte co-culture reduced ESCC cell apoptosis and DNA damage post-radiation.Adipocyte-derived exosomes similarly conferred radioresistance in ESCC cells,decreasing apoptosis and DNA damage post-irradiation.Highthroughput miRNA-sequencing identified miR-660-5p in serum and adipose tissue exosomes.Patients with high expression of serum exosome miR-660-5p showed poor prognosis after radiotherapy.CONCLUSION Adipocyte-derived exosomal miR-660-5p is a potential biomarker for evaluating radiotherapy efficacy in ESCC.

Nomogram based on a novel nutritional immune-inflammatory status score to predict postoperative outcomes in esophageal squamous cell carcinoma

BACKGROUND The relationship between patient nutritional,immune,and inflammatory status is linked to tumor progression and prognosis.However,there are limited studies on the prognosis of esophageal squamous cell carcinoma(ESCC)after surgery based on the comprehensive indicators of these factors.AIM To develop and validate a novel nomogram based on a nutritional immuneinflammatory status(NIIS)score for predicting postoperative outcomes in ESCC.METHODS This retrospective study examined 829 patients with ESCC who underwent radical surgery between June 2016 and June 2020,with 568 patients in the training cohort and 261 patients in the validation cohort.We incorporated comprehensive indicators related to nutrition,immunity,and inflammation to develop the NIIS score, using LASSO regression. Subsequently, a nomogram combining the NIIS score and other clinicopathologicalparameters was developed and validated using calibration curves, time-dependent area under curves, and decisioncurve analysis.RESULTSWe identified eight indicators that constitute the NIIS score. High-risk scores emerged as an independent riskfactor for overall survival [training set HR 2.497 (1.802, 3.458), P < 0.001]. A NIIS nomogram for personalizedprognostic prediction was developed by integrating the NIIS score with clinicopathological variables, yieldingenhanced predictive value relative to individual indicators and the UICC/TNM staging system.CONCLUSIONThe NIIS score provides strong predictive value for postoperative outcomes in ESCC, thus offering a valuable toolfor clinical decision-making.

Safety and effectiveness of induction chemoimmunotherapy followed by definitive radiotherapy or concurrent chemoradiotherapy in esophageal squamous cell carcinoma

BACKGROUND Esophageal squamous cell carcinoma(ESCC)is a common malignancy in China,often diagnosed at an advanced stage,with poor prognosis.Standard treatments such as definitive chemoradiotherapy offer limited survival benefits.Recent advances in immune checkpoint inhibitors combined with chemotherapy have shown promise,but their effectiveness and safety in conjunction with radio-therapy for unresectable ESCC require further exploration.AIM To assess the safety and effectiveness of induction chemoimmunotherapy fo-llowed by definitive radiotherapy or concurrent chemoradiotherapy(CCRT)in locally advanced unresectable ESCC.METHODS This retrospective study included 80 patients with locally advanced unresectable ESCC who underwent induction chemoimmunotherapy followed by definitive radiotherapy,recruited from Zhejiang Cancer Hospital.All patients received 2-4 cycles of chemotherapy plus programmed cell death 1/programmed cell death ligand 1 inhibitor,were re-evaluated to be inoperable,then received definitive radiotherapy or CCRT.Primary endpoint was treatment safety and tolerance.SPSS 26.0 software was used for data analysis.Th Kaplan-Meier method was used for survival analysis.RESULTS Thirty-seven(46.3%)patients received CCRT and 43(53.7%)received radiotherapy alone.The most common treatment-related adverse events included radiation esophagitis(32/80,40.0%)and anemia(49/80,61.3%),with 22(27.5%)experiencing grade≥3 adverse events.No treatment-related deaths occurred.After median follow-up of 16.5 months,the median progression-free survival(PFS)was 14.2 months,and median overall survival(OS)was 19.9 months.The 1-year and 2-year PFS and OS were 55.8%and 31.6%,and 67.5%and 44.1%,respectively.Patients with partial response had better outcomes than those with stable disease:1-year PFS 69.4%vs 43.9%(P=0.011)and OS 83.2%vs 48.8%(P=0.007).Induction therapy effectiveness and immunotherapy maintenance were independent prognostic factors for OS.CONCLUSION Chemotherapy combined with programmed cell death 1/programmed cell death ligand 1 inhibitor followed by definitive radiotherapy or CCRT in patients with locally advanced ESCC was safe and effective.

Development and application prospect of stem cell combined with 3D printing technology for oral disease

With organ transplantation facing many dilemmas,tissue and organ regeneration as an alternative has bright prospects.In regenerative medicine,Three-dimensional(3D)printing technology and stem cells has been widely applied to the treatment of diseases related to tissue or organ replacement in dentistry,respectively.However,there are very few studies on the combination of the two,and even fewer clinical studies have been reported in dentistry.In this review,the current oral tissue engineering in vivo and in vitro based on 3D printing and stem cell technology will be summarized,and the discussion on the development prospects of this research direction will be given.Besides,the working principles and advantages&disadvantages of several types of 3D printers,as well as the mechanism of stem cells in tissue engineering will be elucidated.This review provides clinicians and researchers with the current state of research and trends in the combination of stem cells and 3D printing technology to treat oral-related diseases.In the future,3D bioprinters are poised for ongoing innovation with the advancement of relevant technologies,catalyzing an increase in clinical studies focused on treating oral diseases using stem cells and 3D scaffolds.Consequently,these developments will further advance the field of oral tissue engineering.

The activation of adenosine monophosphate–activated protein kinase inhibits the migration of tongue squamous cell carcinoma cells by targeting Claudin-1 via epithelial–mesenchymal transition

Background:The role of Claudin-1 in tongue squamous cell carcinoma(TSCC)metastasis needs further clarification,particularly its impact on cell migration.Herein,our study aims to investigate the role of Claudin-1 in TSCC cell migration and its underlying mechanisms.Methods:36 TSCC tissue samples underwent immunohistochemical staining for Claudin-1.Western blotting and immunofluorescence analyses were conducted to evaluate Claudin-1 expression and distribution in TSCC cells.Claudin-1 knockdown cell lines were established using short hairpin RNA transfection.Migration effects were assessed through wound healing assays.Furthermore,the expression of EMTassociated molecules was measured via western blotting.Results:Claudin-1 expression decreased as TSCC malignancy increased.Adenosine monophosphate–activated protein kinase(AMPK)activation led to increased Claudin-1 expression and membrane translocation,inhibiting TSCC cell migration and epithelial–mesenchymal transition(EMT).Conversely,Claudin-1 knockdown reversed these inhibitory effects on migration and EMT caused by AMPK activation.Conclusions:Our results indicated that AMPK activation suppresses TSCC cell migration by targeting Claudin-1 and EMT pathways.

Novel insights on oral squamous cell carcinoma management using long non-coding RNAs

Oral squamous cell carcinoma(OSCC)is one of the most prevalent forms of head and neck squamous cell carcinomas(HNSCC)with a poor overall survival rate(about 50%),particularly in cases of metastasis.RNA-based cancer biomarkers are a relatively advanced concept,and non-coding RNAs currently have shown promising roles in the detection and treatment of various malignancies.This review underlines the function of long non-coding RNAs(lncRNAs)in the OSCC and its subsequent clinical implications.LncRNAs,a class of non-coding RNAs,are larger than 200 nucleotides and resemble mRNA in numerous ways.However,unlike mRNA,lncRNA regulates multiple druggable and non-druggable signaling molecules through simultaneous interaction with DNA,RNA,proteins,or microRNAs depending on concentration and localization in cells.Upregulation of oncogenic lncRNAs and downregulation of tumor suppressor lncRNAs are evident in OSCC tissues and body fluids such as blood and saliva indicating their potential as valuable biomarkers.Targeted inhibition of candidate oncogenic lncRNAs or overexpression of tumor suppressor lncRNAs showed potential therapeutic roles in in-vivo animal models.The types of lncRNAs that are expressed differentially in OSCC tissue and bodily fluids have been systematically documented with specificity and sensitivity.This review thoroughly discusses the biological functions of such lncRNAs in OSCC cell survival,proliferation,invasion,migration,metastasis,angiogenesis,metabolism,epigenetic modification,tumor immune microenvironment,and drug resistance.Subsequently,we addressed the diagnostic and therapeutic importance of lncRNAs in OSCC pre-clinical and clinical systems,providing details on ongoing research and outlining potential future directions for advancements in this field.In essence,this review could be a valuable resource by offering comprehensive and current insights into lncRNAs in OSCC for researchers in fundamental and clinical domains.

Galectin 2 regulates JAK/STAT3 signaling activity to modulate oral squamous cell carcinoma proliferation and migration in vitro

Background:Galectin 2(LGALS2)is a protein previously reported to serve as a mediator of disease progression in a range of cancers.The function of LGALS2 in oral squamous cell carcinoma(OSCC),however,has yet to be explored,prompting the present study to address this literature gap.Methods:Overall,144 paired malignant tumor tissues and paracancerous OSCC patient samples were harvested and the LGALS2 expression levels were examined through qPCR and western immunoblotting.The LGALS2 coding sequence was introduced into the pcDNA3.0 vector,to enable the overexpression of this gene,while an LGALS2-specific shRNA and corresponding controls were also obtained.The functionality of LGALS2 as a regulator of the ability of OSCC cells to grow and undergo apoptotic death in vitro was assessed through EdU uptake and CCK-8 assays,and flow cytometer,whereas a Transwell system was used to assess migratory activity and invasivity.An agonist of the Janus Kinase 2(JAK2)/Signal Transducer and Activator of Transcription 3(STAT3)pathway was also used to assess the role of this pathway in the context of LGALS2 signaling.Results:Here,we found that lower LGALS2 protein and mRNA expression were evident in OSCC tumor tissue samples,and these expression levels were associated with clinicopathological characteristics and patient survival outcomes.Silencing LGALS2 enhanced proliferation in OSCC cells while rendering these cells better able to resist apoptosis.The opposite was instead observed after LGALS2 was overexpressed.Mechanistically,the ability of LGALS2 to suppress the progression of OSCC was related to its ability to activate the JAK/STAT3 signaling axis.Conclusion:Those results suggest a role for LGALS2 as a suppressor of OSCC progression through its ability to modulate JAK/STAT3 signaling,supporting the potential utility of LGALS2 as a target for efforts aimed at treating OSCC patients.

TCGA-based analysis of oncogenic signaling pathways underlying oral squamous cell carcinoma

Background:Oral squamous cell carcinoma(OSCC)represents a prevalent malignancy in the oral and maxillofacial area,having a considerable negative impact on both the quality of life and overall survival of affected individuals.Our research endeavors to leverage bioinformatic approaches to elucidate oncogenic signaling pathways,with the ultimate goal of gaining deeper insights into the molecular underpinnings of OSCC pathogenesis,and thus laying the groundwork for the development of more effective therapeutic and preventive strategies.Methods:Differential expression analysis was performed on mRNA data from tumor and normal tissue groups to identify genes associated with OSCC,using The Cancer Genome Atlas database.Predictions of oncogenic signaling pathways linked to differentially expressedmRNAs were made,and these results were presented visually using R software,using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichments.Results:GO and KEGG analyses of 2938 differentially expressed genes in OSCC highlighted their significant involvement in various biological processes.Notably,these processes were related to the extracellular matrix,structural organization,connective tissue development,and cell cycle regulation.Conclusions:The comprehensive exploration of gene expression patterns provides valuable insights into potential oncogenic mechanisms in OSCC.

Diagnostic Role of Computerised Tomography in Mandibular Invasion among Patients with Oral Squamous Cell Carcinoma

Background: Oral cavity malignancy can result from surface epithelium, salivary glands, or submucosal soft tissue. Common symptoms may include non-healing ulcers, slurred speech, dysphagia, neck mass and pain which may indicate cortical invasion. Morbidity and quality of life have been seen to rise with mandibular excision in oral cavity squamous cell carcinoma. Therefore, in order to design the surgery appropriately, it is vital to be aware of the mandibular invasion prior to the procedure. Various researches have been focused on the accuracy of clinical examination and imaging technique in predicting tumour invasion of the mandible in oral malignancy. The goal of this study was to find a correlation between histological assessment, clinical examination, and computed tomography results in patients with mandibular involvement and oral cavity squamous cell carcinoma. Objectives: To determine the sensitivity, specificity, NPV and PPV of CECT and clinical diagnosis in patients with oral squamous cell carcinoma with mandibular invasion. Methods: A cross-sectional observational study was set out to review preoperative clinical and radiological assessment;and post operative histopathological finding of mandibular resection specimen in clinically evaluated and diagnosed cases of oral cavity squamous cell carcinoma (SCC) with mandibular invasion. Results: 43 individuals of oral cavity SCC with mandibular involvement were examined. 12 out of 28 mandibular resections had bone invasion, with numerous tumour entry sites being the most frequent mechanism of invasion, according to post-operative HPE. The positive predictive value (PPV) of contrast enhanced computerised tomography (CECT) scans was 42.8%, as 28 individuals had invasions revealed;sensitivity is almost 100%;specificity is 48.3. Conclusion: Prioritizing the identification of mandibular invasion is essential to enhance the prognosis of patients with oral SCC. There is an urgent necessity to review the usefulness of radiology in the treatment of mandibulectomy. Combination of clinical and radiological examination increases sensitivity and specificity.

Honokiol:a promising small molecular weight natural agent for the growth inhibition of oral squamous cell carcinoma cells

Honokiol （HNK） is a small organic molecule purified from magnolia species and has demonstrated anticancer activities in a variety of cancer cell lines; however, its effect on oral squamous cell carcinoma （OSCC） cells is unknown. We investigated the antitumor activities of HNK on OSCC ceils in vitro for the first time. The inhibitory effects of HNK on the growth and proliferation of OSCC cells were demonstrated via in vitro 3-（4,5-dimethyl thiazol-2-yl）-2,5-diphenyltetrazolium bromide （MTT） and propidium iodide （PI） assays, and the apoptotic cells were investigated by the observation of morphological changes and detection of DNA fragmentation via PI, TdT-mediated dUTP-biotin nick end labeling （TUNEL）, and DNA ladder assays, as well as flow cytometry assay. The results showed that HNK inhibited the growth and proliferation of OSCC cells in vitro in a time and dose-dependent manner. The inhibitory effect was associated with the cell apoptosis induced by HNK, evidenced by the morphological features of apoptotic cells, TUNEL-positive cells and a degradation of chromosomal DNA into small internucleosomal fragments. The study also demonstrated here that the inhibition or apoptosis mediated by 15 μg.mL-1 or 20 μg.mL-1 of HNK were more stronger compared with those of 20 μg-mL-1 5-fluorouracil （5-Fu, the control） applied to OSCC cells, when the ratio of OSCC cell numbers were measured between the treatment of different concentrations of HNK to the 5-Fu treatment for 48 h. HNK is a promising compound that can be potentially used as a novel treatment agent for human OSCC.

Squamous cell carcinoma of the oral cavity and circulating tumour cells

Due to a lack of substantial improvement in the outcome of patients suffering from oral squamous cell carcinoma(OSCC) during the past decades, current staging methods need to be revised. This disease is associated with poor survival rates despite considerable advances in diagnosis and treatment. The early detection of metastases is an important indicator of survival, prognosis and relapse. Therefore, a better understanding of the mechanisms underlying metastasis is crucial. Exploring alternative measures apart from common procedures is needed to identify new prognostic markers. Similar to previous findings predominantly for other solid tumours, recently published studies demonstrate that circulating tumour cells(CTCs) and disseminated tumour cells(DTCs) might serve as prognostic markers and could supplement routine staging in OSCC. Thus, the detection of CTCs/DTCs is a promising tool todetermine the individual need for therapeutic intervention. Encouraging results and new approaches point to the future use of targeted therapies for OSCC, an exceedingly heterogeneous subgroup of head and neck cancer. This review focuses on summarising technologies currently used to detect CTCs/DTCs. The translational relevance for OSCC is highlighted. The inherent challenges in detecting CTCs/DTCs will be emphasised.

MiR-210 expression reverses radioresistance of stem-like cells of oesophageal squamous cell carcinoma

AIM: To investigate the expression of miR-210 and the role it plays in the cell cycle to regulate radioresistance in oesophageal squamous cell carcinoma(ESCC). METHODS: Mi R-210 expression was evaluated in 37 pairs of ESCC tissues and matched para-tumorous normal oesophageal tissues from surgical patients who had not received neoadjuvant therapy, and in the cells of two novel radioresistant cell lines, TE-1R and Eca-109 R, using quantitative reverse transcription-polymerase chain reaction(q RT-PCR). The transient up-regulation of mi R-210 expression in TE-1R and Eca-109 R cells was studied using liposomes and was confirmed using qR T-PCR. The rate of cell survival after a series of radio-treatment doses was evaluated using the cloneformation assay. Flow cytometry was used to detect the changes to the cell cycle patterns due to radiation treatment. RT-PCR and Western blot were used to detect the expression of ataxia telangiectasia mutated(ATM) and DNA dependent protein kinase(DNA-PKcs) after irradiation, and the cell sphere formation assay was used to evaluate the proliferative ability of the cancer stem-like cells.RESULTS: The level of mi R-210 expression was significantly decreased, by 21.3% to 97.2%, with the average being 39.2% ± 16.1%, in the ESCC tissues of most patients(81.1%, 30 of 37 vs patients with high mi R-210 expression, P < 0.05). A low level of expression of miR-210 was correlated with a poorly differentiated pathological type(P < 0.01) but was not correlated with the T-stage or lymph node infiltration(both P > 0.05). Early local recurrences(< 18 mo, n = 19) after radiotherapy were significantly related with low miR-210 expression(n = 13, P < 0.05). The level of mi R-210 was decreased by approximately 73%(vs TE-1, 0.27 ± 0.10, P < 0.01) in the established radioresistant TE-IR cell line and by 52%(vs Eca-109, 0.48 ± 0.17, P < 0.05) in the corresponding Eca-109 R line. Transient transfection with a mi R-210 precursor increased the level of mi R-210 expression, leading to a significant increase in cell survival after radiotherapy(P < 0.05). Twenty-four hours after radiation, the proportion of pmiR-210 cells in S phase was increased(vs control cells, 30.4% ± 0.4%, and vs untreated TE-1R cells, 23.3% ± 0.7%, P < 0.05 for both). The levels of DNA-PKcs(0.21 ± 0.07) and ATM(0.12 ± 0.03, P < 0.05) proteins were significantly lower in the PmiR-210 cells than in control cells, but no differences were found in the levels of the corresponding mR NAs in the two cell types(P > 0.05 for all). Exogenous mi R-210 expression decreased the diameter of pmi R-210 cell spheres(vs control cells, 0.60 ± 0.14, P < 0.05).CONCLUSION: Mi R-210 expression is negatively correlated with the pathological type and the local survivalrate after radiotherapy, and high expression of miR-210 may reverse the radioresistance of ESCC stem-like cells.

NEDD9 promotes cancer stemness by recruiting myeloid-derived suppressor cells via CXCL8 in esophageal squamous cell carcinoma

Objective:Esophageal squamous cell carcinoma(ESCC)has high morbidity and mortality rates worldwide.Cancer stem cells(CSCs)may cause tumor initiation,metastasis,and recurrence and are also responsible for chemotherapy and radiotherapy failures.Myeloid-derived suppressor cells(MDSCs),in contrast,are known to be involved in mediating immunosuppression.Here,we aimed to investigate the mechanisms of interaction of CSCs and MDSCs in the tumor microenvironment.Methods:ESCC tissues and cell lines were evaluated.Neural precursor cell expressed,developmentally downregulated 9(NEDD9)was knocked down and overexpressed by lentiviral transfection.Quantitative PCR,Western blot,immunohistochemistry,cell invasion,flow cytometry,cell sorting,multiplex chemokine profiling,and tumor growth analyses were performed.Results:Microarray analysis revealed 10 upregulated genes in esophageal CSCs.Only NEDD9 was upregulated in CSCs using the sphere-forming method.NEDD9 expression was correlated with tumor invasion(P=0.0218),differentiation(P=0.0153),and poor prognosis(P=0.0373).Additionally,NEDD9 was required to maintain the stem-like phenotype.Screening of chemokine expression in ESCC cells with NEDD9 overexpression and knockdown showed that NEDD9 regulated C-X-C motif chemokine ligand 8(CXCL8)expression via the ERK pathway.CXCL8 mediated the recruitment of MDSCs induced by NEDD9 in vitro and in vivo.MDSCs promoted the stemness of ESCC cells through NEDD9 via the Notch pathway.Conclusions:As a marker of ESCC,NEDD9 maintained the stemness of ESCC cells and regulated CXCL8 through the ERK pathway to recruit MDSCs into the tumor,suggesting NEDD9 as a therapeutic target and novel prognostic marker for ESCC.

Sphere-forming-like cells(squamospheres) with cancer stem-like cell traits from VX2 rabbit buccal squamous cell carcinoma

Previous studies have demonstrated that spheroid type cells grown under suspension culture conditions have cancer stem cell（CSC） traits in a number of cancers, but this phenomenon has not yet been reported in the VX2 rabbit oral cancer model. Hence, this study aimed to study the spheroid cells from VX2 rabbit buccal squamous cell carcinomas（SCCs） and assess their CSC characteristics. Five adult male New Zealand white outbred rabbits were used to generate VX2 rabbit buccal SCC. Sphere-forming cell culture was performed for the VX2 rabbit buccal SCC specimens. The self-renewal capability; cluster of designation（CD） 44, CD133, acetaldehyde dehydrogenase 1（ALDH1）, B cell-specific Moloney murine leukemia virus integration site 1（Bmi-1）, Nestin, octamer-binding transcription factor 4（Oct4）and reduced expression protein-1（Rex-1） expression with reverse transcription-polymerase chain reaction（RT-PCR）; chemoresistance to cisplatin and 5-fluorouracil; and in vivo tumorigenicity of spheroid cell transplantation in nude mice were evaluated to determine the CSC characteristics of the resulting spheroid cells. We successfully obtained spheroid cells from the VX2 rabbit OSCC tissues. The spheroid cells exhibited CSC traits, including the expression of CSC and stem cell markers（CD44, Bmi-1, Nestin, Oct4 and Rex-1）, capacity to generate new spheroid colonies within 1 week of reseeding from single-dissociated spheroid cells, chemoresistance capacity and generation of tumour xenografts（with histological features resembling those of the original VX2 rabbit buccal SCC） from the transplantation of 103 undifferentiated spheroid cells into nude mice. In summary, we demonstrated that spheroid cells with CSC cell traits can be derived from VX2 rabbit buccal SCCs, indicating that this animal cancer model is applicable for studying CSCs in human oral cancers.

Molecular signaling in cancer stem cells of tongue squamous cell carcinoma:Therapeutic implications and challenges

Head and neck squamous cell carcinoma is the seventh most common cancer worldwide with high mortality rates.Amongst oral cavity cancers,tongue carcinoma is a very common and aggressive oral cavity carcinoma.Despite the implementation of a multimodality treatment regime including surgical intervention,chemo-radiation as well as targeted therapy,tongue carcinoma shows a poor overall 5-year survival pattern,which is attributed to therapy resistance and recurrence of the disease.The presence of a rare population,i.e.,cancer stem cells(CSCs)within the tumor,are involved in therapy resistance,recurrence,and distant metastasis that results in poor survival patterns.Therapeutic agents targeting CSCs have been in clinical trials,although they are unable to reach into therapy stage which is due to their failure in trials.A more detailed understanding of the CSCs is essential for identifying efficient targets.Molecular signaling pathways,which are differentially regulated in the CSCs,are one of the promising targets to manipulate the CSCs that would provide an improved outcome.In this review,we summarize the current understanding of molecular signaling associated with the maintenance and regulation of CSCs in tongue squamous cell carcinoma in order to emphasize the need of the hour to get a deeper understanding to unravel novel targets.

POLE2 Regulates Apoptosis of Oral Squamous Cell Carcinoma Cells through the PI3K/AKT Signaling Pathway

Objective Oral squamous cell carcinoma(OSCC)is the most common malignant tumor of the head and neck,but its occurrence and progression mechanisms remain unclear.In addition-there is a lack of effective targeting drugs.The second major subunit of DNA polymerase(POLE2)catalyzes the prolongation of new strand replication and modifies exonuclease domain activity.Our previous study found that POLE2 was associated with OSCC progression,but the mechanism remains unclear.Methods The expression of POLE2 in OSCC tissues was detected using immunological assays.Mann-Whitney U analysis was used to investigate the relationship between POLE2 gene expression and tumor classification and prognosis of OSCC.POLE2 expression was inhibited in OSCC cells,and the effects of gene and protein expression were detected using RT-PCR and Western blotting.The POLE2 knockout model was constructed by transfecting a lentiviral vector.Cell proliferation,apoptosis,and migration were detected using various assays including colony formation,MTT,flow cytometry,wound healing assay,Transwell assay,and the Human Apoptosis Antibody Array.The animal model of OSCC was established by subcutaneous injection of transfected HN6 into 4-week-old female nude mice.After 30 days,tumors were removed under anesthesia and tumor weight and dimension were recorded.Tumor cell proliferation was analyzed using Ki67 staining.Results POLE2 gene levels were significantly higher in the OSCC tissues than in the normal tissues.In addition,POLE2 gene levels were statistically correlated with tumor classification and prognosis.Silencing POLE2 inhibited the proliferation of oral cancer cells and promoted apoptosis in vitro.Animal experiments also supported a positive correlation between POLE2 and OSCC tumor formation.We further demonstrated that POLE2 could upregulate the expression of apoptosis-related proteins such as caspase-3,CD40,CD40L,DR6,Fas,IGFBP-6,p21,and SMAC.In addition,POLE2 regulated OSCC development by inhibiting the PI3K/AKT signaling pathway.Conclusion POLE2 is closely related to the progression of OSCC.Thus,POLE2 may be a potential target for OSCC treatment.