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.

miR-221/222/PUMA Axis Promotes Oral Squamous Cell Carcinoma Apoptosis

Background: To investigate the therapeutic activity of the miR-221/222 inhibitor against OSCC in vitro and in vivo. Materials and Methods: HSC3 and HSC6 were treated with miR-221/222 inhibitor and the empty vector respectively. After the recombinants were transfected into HSC3 and HSC6 with LipofectamineTM MAX, the expression of miR-221/222 and PUMA was analyzed by RT-PCR. The proliferation and migration of HSC3 and HSC6 were detected by CCK-8 assay and Wound-healing assay. Cell cycle and apoptosis were detected by flow cytometry. The effect of the miR-221/222 inhibitor was also assessed in OSCC xenografts in BALB/c-nu mice. Results: Transfection of the miR-221/222 inhibitor increased cell apoptosis and upregulated PUMA expression in OSCC cell lines HSC3 and HSC6 with the significantly reduced expression of miR-221 and miR-222. Furthermore, the miR-221/222 inhibitor suppressed cell growth and invasion and blocked the cell cycle at the G1 phase. Obvious anti-tumor activity was achieved in BALB/c-nu mice by treatment with the miR-221/222 inhibitor, together with the upregulation of PUMA protein in tumors retrieved from the mice. Conclusions: There was a significant inhibitory effect of the miR-221/222 inhibitor on the growth of OSCC both in vitro and in vivo, and there might be a regulatory loop between miR-221/222 and PUMA. These findings demonstrated that downregulation of miR-221/222 could induce cell apoptosis, and it might be considered as a candidate target for gene therapy of OSCC.

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.

Effects of IL-6/JAK2/STAT3 on the Biological Behavior of Oral Squamous Cell Carcinoma

Objective:To investigate the effect of interleukin 6/Janus kinase 2/signal transducer and activator of transcription 3(IL-6/JAK2/STAT3)on the biological behavior of oral squamous cell carcinoma(OSCC).Methods:OSCC cells were transfected with the designed lentiviral vector plasmid pGMLV-SB3(experimental group)and the corresponding negative control plasmid pGMLV-SB3-shNC(control group);48 hours after transfection,a liposome transfection kit(Sigma,USA)was used for lentivirus packaging;after virus packaging,a medium containing pGMLV-SB3 lentiviral vector was added and cultured for 24 h;the cells were harvested,and RNA was extracted;Transwell chamber assay(Sigma,USA)was used to detect cell migration and invasion ability;dot-enzyme-linked immunosorbent assay(ELISA)kit was used to detect the level of interleukin 6(IL-6)in the culture supernatant,while serum IL-6 level was measured by ELISA.Results:The expressions of IL-6,JAK2,and STAT3 in the experimental group were significantly raised,as compared to the control group(P<0.05);the apoptosis rate of OSCC cells in the experimental group,which was detected by flow cytometry 48 h after transfection,was significantly higher than that of cells in the control group(P<0.05);and there was a significant improvement in the experimental group’s cell migration and invasion ability,as compared to that of the control group(P<0.05).Conclusion:The IL-6/JAK2/STAT3 signaling pathway plays an important role in the migration and invasion of OSCC cells.Inhibiting the expression of IL-6 can inhibit the growth and proliferation of OSCC cells as well as reduce their ability to invade and migrate.These results provide a new target for the treatment of OSCC.

The Effect of MMP-9 Inhibitors on the Biological Behavior of Human Oral Squamous Cell Carcinoma SCC15 Cell Line Through PI3K/Akt Signaling Pathway

Objective:To investigate the effect of MMP-9 inhibitor(Mki67)on the biology of human oral squamous cell carcinoma SCC15 cell line and to explore its mechanism of action through PI3K/Akt signaling pathway.Methods:SCC15 cells were extracted,and the supernatant was discarded.The cells were then rinsed twice with PBS,and 0,2.5,5,and 10μL of Mki67(50 mg/mL)were added to the culture respectively.The inhibition rate of cell proliferation was detected by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide(MTT)method,and the cell migration was measured by Transwell chamber test.The cell apoptosis rate was detected by cytometry,and the p-Akt protein content in the cells of each group was determined by a double-antibody sandwich enzyme-linked immunosorbent assay(ELISA)kit.Results:The cell proliferation rates of the 2.5μL,5μL,and 10μL dose groups were all lower than the 0μL group(P<0.05)before treatment,and the cell proliferation rates in the 2.5μL,5μL,and 10μL dose groups decreased overtime(P<0.05).After 24 h,with the increase of Mki67 concentration,the number of migration and invasion gradually decreased(P<0.05),and the number of apoptosis gradually increased(P<0.05);besides,the relative expression of MMP-9,PI3K,and Akt mRNA decreased gradually(P<0.05),and the expression level of Akt mRNA was not statistically significant(P>0.05).Conclusion:MMP-9 inhibitor(Mki67)can inhibit the proliferation and migration of SCC15 cell line and induce apoptosis,and its mechanism of action may be related to the inhibition of PI3K/Akt signaling pathway.

Upregulation of vimentin and aberrant expression of E-cadherin /beta-catenin complex in oral squamous cell carcinomas:correlation with the clinicopathological features and patient outcome

Oral squamous cell carcinoma is a challenging oncology problem.A reliable biomarker for metastasis or high-risk prognosis in oral cancer patients remains undefined.Using quantitative immunohistochemistry,we examined the expression of vimentin,E-cadherin,and beta-catenin in 83 oral squamous cell carcinoma patients,and the relationships between the expression of these markers and specific clinicopathological features were analysed.The high expression of vimentin was observed in 23 of 43(53%) tumours from patients who eventually developed a recurrent tumour and was associated with recurrence and death(P < 0.001 and < 0.001,respectively).The decreased expression of E-cadherin was observed in 36 of 43(84%) tumours from patients who eventually developed a recurrent tumour and was also associated with recurrence and death(P < 0.001 and < 0.001,respectively).Although no correlation between beta-catenin expression in whole-tumour sections and clinicopathological features was observed,decreased beta-catenin expression at the tumour invasive front was closely associated with recurrence and death(P=0.002 and 0.002,respectively).The expression of vimentin and that of E-cadherin were associated with survival and were independent prognostic factors in univariate and multivariate analyses.Our data show that the overexpression of vimentin was closely associated with recurrence and death in oral squamous cell carcinoma patients.The combination of the upregulation of vimentin and aberrant expression of E-cadherin/beta-catenin complexes at the tumour invasive front may provide a useful prognostic marker in oral squamous cell carcinoma.

Analysis of P53 Mutation and Invasion Front Grading in Oral Squamous Cell Carcinomas

We examined P53 mutation and invasion front grading (IFG) in 30 cases of oral squamous cell carcinomas (OSCCs). The association of P53 mutation and IFG scores with clinicopa-thological parameters was evaluated. P53 mutation existed in exon 5-8 in 15 out of the 30 OSCCs (50%). The incidence of P53 mutation was not associated with age, gender, N value and TNM stage. However, there was a significant correlation between P53 mutation and T value (P=0.046). There were no statistically significant correlations among the clinicopathological parameters and IFG. Interestingly, The IFG score in OSCCs with P53 mutation was significantly higher than that in OSCCs without P53 mutation (P<0.001). These results suggest that the high incidence of P53 mutation is a major mechanism of OSCC carcinogenesis. The presence of P53 mutation indicates the most anaplastic fields in the invasive areas of the tumors, which may predict poor prognosis for the patients.

白藜芦醇通过NF-κB相关通路对顺铂引起的OSCC细胞化疗耐药性的影响

目的:观察白藜芦醇对顺铂(cisplatin,DDP)引起的口腔鳞状细胞癌(oral squamous cell carcinoma,OSCC)细胞化疗耐药性的影响,并探讨相关机制。方法:取对数期CAL-27/DDP细胞,随机分为对照组(常规培养)、白藜芦醇组(加入白藜芦醇200μmol/L)、激动剂组[加入肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)10 ng/mL]、白藜芦醇联合激动组(加入白藜芦醇200μmol/L、TNF-α10 ng/mL)。各组均培养48 h用于后续实验。MTT法检测细胞增殖抑制率;双染法检测细胞凋亡率;检测细胞内DDP蓄积与潴留;Western blotting法检测细胞P糖蛋白(P-glycoprotein,P-gp)、拓扑异构酶Ⅱ(topoisomorasesⅡ,TopoⅡ)、核因子-κB(nuclear factor-κB,NF-κB)p65、磷酸化NF-κB(phosphorylated-NF-κB,p-NF-κB)p65、核因子抑制蛋白α(inhibition of NF-κB,IκBα)、磷酸化IκBα(phosphorylated-IκBα,p-IκBα)蛋白表达量。结果:与对照组比较,白藜芦醇组增殖抑制率、凋亡率、药物蓄积量、药物潴留量、TopoⅡ蛋白表达升高,P-gp、p-NF-κB p65/NF-κB p65、p-IκBα/IκBα蛋白表达量的比值降低(P<0.05),激动剂组增殖抑制率、凋亡率、药物蓄积量、药物潴留量、TopoⅡ蛋白表达降低,P-gp、p-NF-κB p65/NF-κB p65、p-IκBα/IκBα蛋白表达量的比值升高(P<0.05);与白藜芦醇组比较,白藜芦醇联合激动组增殖抑制率、凋亡率、药物蓄积量、药物潴留量、TopoⅡ蛋白表达降低,P-gp、p-NF-κB p65/NF-κB p65、p-IκBα/IκBα蛋白表达量的比值升高(P<0.05);与激动剂组比较,白藜芦醇联合激动组增殖抑制率、凋亡率、药物蓄积量、药物潴留量、TopoⅡ蛋白表达升高,P-gp、p-NF-κB p65/NF-κB p65、p-IκBα/IκBα蛋白表达量的比值降低(P<0.05)。结论:白藜芦醇可降低DDP引起的OSCC细胞化疗耐药性,其作用机制可能与抑制NF-κB通路有关。

COX-2, MMP-7 expression in oral lichen planus and oral squamous cell carcinoma

Objective: To observe cyclooxygenase (COX)-2 expression in normal oral mucosa (NOM), oral lichen planus (OLP) and oral squamous cell carcinoma (OSCC) and explore its significance in the incidence of oral cancer. Methods: The immunohistochemical method and RT-PCR method were applied to detect the expression of COX-2 and MMP-7 in 10 cases with NOM, 33 cases of with OLP and 38 cases with OSCC. Results: The expression of COX-2 mRNA in OSCC tissues (68.4%, 26/38) was significantly higher than in the OLP (24.2%, 8/33) and NOM (0.0%, 0/10) ( P<0.01). The expression of MMP-7 mRNA in OSCC tissues (65.8%, 25/38) was significantly higher than in the OLP (30.3%, 10/33) and NOM (0.0%, 0/10) ( P<0.01). The expression of MMP-7 in OLP was significantly higher than in the NOM ( P<0.05). There was no significant expression of COX-2 protein in NOM, and the positive rate was 42.4% (14/33) and 89.5% (34/38) in OLP and OSCC group, respectively. The COX-2 expression in cancer tissues was significantly higher than in NOM and OLP ( P<0.05). The MMP-7 protein expression in cancer tissues (84.2%, 32/38) was significantly higher than in NOM (10.0%, 1/10) and in OLP (42.4%, 14/33), and the positive rate in OLP was significantly higher than in NOM ( P<0.01). The COX-2 expression was associated with clinical stage ( P<0.05), the MMP-7 expression was associated with clinical stage and lymph node metastasis ( P<0.05). The expressions of COX-2 and MMP-7 mRNA were positively correlated with OSCC. Conclusions: The abnormal expressions of COX-2 and MMP-7 are closely related to the biological behavior of OSCC, the MMP-7 may be induced by COX-2, and further lead to the invasion and metastasis of OSCC.

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.

A review of clinical and histological parameters associated with contralateral neck metastases in oral squamous cell carcinoma

Oral squamous cell carcinoma （OSCC） has a high incidence of cervical micrometastases and sometimes metastasizes contralaterally because of the rich lymphatic intercommunications relative to submucosal plexus of oral cavity that freely communicate across the midline, and it can facilitate the spread of neoplastic cells to any area of the neck consequently. Clinical and histopathologic factors continue to provide predictive information to contralateral neck metastases （CLNM） in OSCC, which determine prophylactic and adjuvant treatments for an individual patient. This review describes the predictive value of clinical-histopathologic factors, which relate to primary tumor and cervical lymph nodes, and surgical dissection and adjuvant treatments. In addition, the indications for elective contralateral neck dissection and adjuvant radiotherapy （aRT） and strategies for follow-up are offered, which is strongly focused by clinicians to prevent later CLNM and poor prognosis subsequently.

In vitro effect of iASPP on cell growth of oral tongue squamous cell carcinoma

iASPP is an inhibitory member of the apoptosis-stimulating proteins of P53 （ASPP） family. iASPP is over expressed in several malignant tumors and potentially affects cancer progression. However, the expression and potential role of iASPP in oral tongue squamous cell carcinoma （OTSCC） have not been addressed. In our study, we detected iASPP expression in OTSCC by immunohistochemistry, iASPP expression is up-regulated in OTSCC tissues. Moreover, in clinical pathology specimens, we found that increased iASPP expression correlates with poor differentiation and lymph node metastasis. Using multicellular tumor spheroids （MTS） and flow cytometry, we demonstrated that iASPP down-regulation arrests OTSCC cells at the G0/G1 phase, induces OTSCC cell apoptosis and inhibits OTSCC cell proliferation. These results indicate that iASPP plays a significant role in the progression of OTSCC and may serve as a biomarker or therapeutic target for OTSCC patients.

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.

Differential mRNA expression profiling of oral squamous cell carcinoma by high-throughput RNA sequencing

Differentially expressed genes are thought to regulate the development and progression of oral squamous cell carcinomas （OSCC）. The purpose of this study was to screen differentially expressed mRNAs in OSCC and matched paraneoplastic normal tissues, and to explore the intrinsic mechanism of OSCC development and progres- sion. We obtained the differentially expressed mRNA expression profiles in 10 pairs of fresh-frozen OSCC tissue specimens and matched paraneoplastic normal tissue specimens by high-throughput RNA sequencing. By using Gene Ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes （KEGG） pathway enrichment analyses, the functional significance of the differentially expressed genes were analyzed. We identified 1,120 sig- nificantly up-regulated mRNAs and 178 significantly down-regulated mRNAs in OSCC, compared to normal tissue. The differentially expressed mRNAs were involved in 20 biological processes and 68 signal pathways. Compared to adjacent normal tissue, the expression of MAGEAll was up-regulated; TCHH was down-regulated. These find- ings were verified by real-time PCR. These differentially expressed mRNAs may function as oncogenes or tumor suppressors in the development and progression of OSCC. This study provides novel insights into OSCC. However, further work is needed to determine if these differentially expressed mRNAs have potential roles as diagnostic bio- markers and candidate therapeutic targets for OSCC.

The recurrence and survival of oral squamous cell carcinoma: a report of 275 cases

Oral squamous cell carcinoma(OSCC) is a common malignant tumor of the head and neck, and recurrence is an important prognostic factor in patients with OSCC. We explored the factors associated with recurrence of OSCC and analyzed the survival of patients after recurrence. Clinicopathologic and follow-up data of 275 patients with OSCC treated by surgery in the Cancer Institute and Hospital of Tianjin Medical University between 2002 and 2006 were analyzed. Recurrence factors were analyzed with Chisquare or Fisher′s exact test and multivariate analysis. The prognosis of patients after recurrence was analyzed with the Kaplan-Meier method and log-rank test. The recurrence rate was 32.7%. The recurrence time ranged from 2 to 96 months, with a median of 14 months. Univariate analysis showed that T stage, degree of differentiation, pN stage, flap application, resection margin, and lymphovascular invasion were factors of recurrence (P<0.05). Multivariate analysis showed that T stage, degree of differentiation, and pN stage were independent factors of recurrence (P<0.001). The differences in gender, age, tumor site, region of lymph node metastasis, and perineural invasion between the recurrence and non-recurrence groups were not significant (P>0.05). Kaplan-Meier and log-rank tests showed that the 2- and 5-year survival rates were significantly lower in the recurrence group than in non-recurrence group(67.6% vs. 88.0%, 31.8% vs. 79.9%, P<0.001). Therefore, to improve prognosis, we recommend extended local excision, flap, radical neck dissection, and adjuvant chemoradiotherapy for patients more likely to undergo recurrence.

Anti-Cancer Effects of Cordycepin on Oral Squamous Cell Carcinoma Proliferation and Apoptosis in Vitro

Cordycepin is an active component of parasitic fungus, Cordyceps militaris, and investigated for its pharmacologic efficacy. Increasing evidence supports the anti-tumoral effects of Cordycepin in various types of human solid tumors. We sought to determine the effects of Cordycepin on oral squamous cell carcinoma in vitro and in vivo. Two oral squamous cell carcinoma cell lines, KB and HSC3, were used in this study. Cells were treated with Cordycepin or diluent, followed by determinations of proliferation by sulforhodamine method and apoptosis by TUNEL assay in vitro. For in vivo experiments, tumor cells were transplanted into nude mice, followed by treatment with Cordycepin or control diluent. In addition, cells were examined for expression of adenosine receptor isotypes, and tested whether cordycepin-induced effects were mediated through adenosine receptors by combinatorial treatment of cordycepin and antagonists specific to each isotype of adenosine receptors. Two cell lines expressed protein of all types of adenosine receptors stronger than normal oral keratinocytes. Cordycepin showed anti-proliferating effect and apoptotic effect on both cell lines in vitro in a dose dependent manner. However, any adenosine receptors did not reverse the effect of cordycepin. In our in vivo experiments, cordycepin failed to decrease the tumor volume significantly, and failed to induce more apoptosis of tumor cells. Cordycepin has anti-proliferating effect and induces apoptosis not mediated by adenosine receptor on oral squamous cell carcinoma cells in vitro. However, in vivo results suggest that cordycepin in itself has a limited value as a novel chemotherapeutic agent for oral squamous cell carcinoma.

Oral Squamous Cell Carcinoma: Epidemiology, Clinical Presentation and Treatment

Squamous cell carcinoma accounts for 90% of all oral cancers. It may affect any anatomical site in the mouth, but most commonly the tongue and the floor of the mouth. It usually arises from a pre-existing potentially malignant lesion, and occasionally de novo;but in either case from within a field of precancerized epithelium. The use of tobacco and betel quid, heavy drinking of alcoholic beverages and a diet low in fresh fruits and vegetables are well known risk factors for oral squamous cell carcinoma. Important risk factors related to the carcinoma itself that are associated with a poor prognosis include large size of the tumour at the time of diagnosis, the presence of metastases in regional lymphnodes, and a deep invasive front of the tumour. Squamous cell carcinoma is managed by surgery, radiation, and chemotherapy singularly or in combination;but regardless of the treatment modality, the five-year survival rate is poor at about 50%. This can be attributed to the fact that about two-thirds of persons with oral squamous cell carcinoma already have a large lesion at the time of diagnosis.

Human Papillomavirus as an Independent Predictor in Oral Squamous Cell Cancer

Aim There is an increasing evidence for the role of high risk human papillomavirus （HPV） in the pathogenesis of oral squamous cell carcinoma （OSCC）. The purpose of this study is to evaluate the relevance of HPV infection to the survival and prognosis of OSCC. Methodology Fifty-two patients with OSCC were followed from 4 to 88 months with a median of 50.7 months. HPV DNA was identified in formalin-fixed, paraffin-embedded tumor specimens by nested PCR with MY09/MY11 and GP5^＋/GP6^＋ primer pairs and the HPV genotype was determined by direct DNA sequencing. Association between the HPV status and risk factors for cancer as well as tumor-host characteristics were analyzed.Survival curves were calculated by the Kaplan-Meier method and analyzed using the log-rank test. Results HPV was found in 40.4% of the tumors with HPV16 accounting for 63.5%, HPV18 for 30.8%, HPV6 for 3.9% and HPVll for 1.8%. No infection with more than one HPV genotype was detected. HPV infection was significantly associated with poor histological grade, TNM stage Ⅰ -Ⅱ, alcohol usage and no smoking status. Multivariate analysis showed that HPV had an independent prognostic effect on the overall survival after adjusting other confounding factors such as histological grade, TNM stage and tobacco usage. The presence of HPV was significantly correlated with a better survival in patients with OSCC. Conclusion HPV infection can act as an independent predictor for the survival and prognosis of OSCC.