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.

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.

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.

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.

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.

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.

Diagnostic delay in oral squamous cell carcinoma: the role of cognitive and psychological variables

This retrospective study investigated, in two cohorts of subjects living in Southern Italy and awaiting treatment for oral squamous cell carcinoma （OSCC）, the variables related to diagnostic delay ascribable to the patient, with particular reference to the cognitive and psychological ones. A total of 156 patients with OSCC （mean age： 62 years, M/F： 2.39 ： 1） were recruited at the Universities of Palermo and Naples. Risk factors related to patient delay included： sociodemographic, health-related, cognitive and psychological variables. The analysis was conducted by considering two different delay ranges： dichotomous （≤1 month vs. 〉 1 month） and polytomous （〈1 month, 1-3 months, 〉3 months） delay. Data were investigated by univariate and multivariate analyses and a Pvalue≤0.05 was considered statistically significant. For both delay measurements, the most relevant variables were： ＇Personal experience of cancer＇ （dichotomous delay： P=0.05, odds ratio （0R）=0.33, 95% confidence interval （CI）=0. 11-0.99; polytomous delay： P=0.006, Chi-square= 10.224） and ＇Unawareness＇ （dichotomous delay： P〈0.01, 0R=4.96, 95% CI--2.16-11.37; polytomous delay： P=0.087, Chi-square=4.77）. Also ＇Denial＇ （P〈0.01, 0R=6.84, 95% CI=2.31-20.24） and ＇Knowledge of cancer＇ （P=0.079, Chi-square=8.359） were found to be statistically significant both for dichotomous and for polytomous categorization of delay, respectively. The findings of this study indicated that, in the investigated cohorts, the knowledge about cancer issues is strongly linked to the patient delay. Educational interventions on the Mediterranean population are necessary in order to increase the patient awareness and to emphasize his/her key role in early diagnosis of OSCC.

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.

Expression of p53, p21^(CIP1/WAF1) and eIF4E in the adjacent tissues of oral squamous cell carcinoma:establishing the molecular boundary and a cancer progression model

The present study evaluated the expression of key molecules and the status of DNA in both oral squamous cell carcinoma（OSCC） and adjacent tissues to establish a molecular surgical boundary and provide a cancer progression model. Biopsy samples from 50 OSCC patients were divided into T（cancer）, P1（0–0.5 cm）, P2（0.5–1 cm）, P3（1–1.5 cm） and P4（1.5–2 cm） groups based on the distances from the visible boundary of the primary focus. Twenty samples of normal mucosa were used as controls. We used immunohistochemical staining and flow cytometry to evaluate p53, p21CIP1/WAF1, e IF4 E and Ki-67 expression and to determine DNA status, respectively. Sub-mucosal invasion was present in the P1 and P2 groups as determined by haematoxylin and eosin staining.Mutant p53 expression decreased gradually from cancerous to normal mucosae, whereas p21CIP1/WAF1 expression displayed an opposite trend. e IF4 E expression decreased from cancerous to normal mucosae. Ki-67 expression, the heteroploidy ratio, S-phase fraction and proliferative index decreased gradually with the distance from the tumour centre. Based on these results, we suggest that the resection boundary in OSCC surgery should be beyond 2 cm from the tumour. Additionally, the adjacent tissues of the primary focus could be used as a model for assessing cancer progression.

Identification of microRNA-21 as a valuable diagnostic marker of oral squamous cell carcinoma and potential target

Objective The aim of the study was to summarize the diagnostic value of miR-21 as a biomarker in oral squamous cell carcinoma(OSCC)using a review of the literature and data from the cancer genome atlas(TCGA)database.Methods Data from TCGA database was sorted and analyzed by bioinformatics to determine the expression level of miR-21 in OSCC.Further,we searched for relevant articles in Embase,PubMed/Medline,Scopus,and Web of Science published before March 2021,extracted the data,and conducted quality assessment.The bivariate meta-analysis model with Stata 16.0 was used to analyze the diagnostic value of miR-21 for OSCC.Results A total of 304 related articles were identified,and seven were selected for meta-analysis.The diagnostic results after analysis were as follows:sensitivity 0.76[95%confidence interval(CI),0.57-0.88];specificity 0.77(95%CI,0.58-0.89);positive likelihood ratio 3.34(95%CI,1.58-7.08);negative likelihood ratio 0.31(95%CI,0.15-0.63);diagnostic odds ratio 10.75(95%CI,2.85-40.51);and area under the curve 0.83(95%CI,0.80-0.86).The Deeks’funnel chart showed that there was no potential bias(P=0.54).Prediction analysis of the potential target genes of miR-21 was performed via the biological website,and DAVID was used to cross target genes for gene ontology(GO)annotation function analysis.Conclusion The results showed that miR-21-3p and miR-21-5p were significantly more highly expressed in OSCC tissues than in normal tissues(P<0.05),and the results of the meta-analysis indicated that they could be used as potential biomarkers in the diagnosis of OSCC.In addition,58 potential target genes of miR-21 were significantly enriched in 28 GO annotation functional pathways,which provided a biological basis for further clinical diagnostic value research.

Development of a Photodynamic Diagnosis Method for Oral Squamous Cell Carcinoma Using 5-Aminolevulinic Acid and a Luminescence Plate Reader

Purpose: To establish a simple and accurate photodynamic diagnosis (PDD) method for oral squamous cell carcinoma (OSCC). Methods: OSCC cell lines HSC-2, HSC-3, HSC-4, and Sa3, and normal human oral keratinocytes (HOK) were used. First, we examined the amount of cells needed to detect differences in fluorescence intensities for PDD. OSCC cell lines were adjusted to concentrations of 1 × 104 (104), 1 × 105 (105), and 1 × 106 (106) cells/ml. The experimental groups comprised a group with 5-aminolevulinic acid (5-ALA (+)), and a group without 5-ALA (5-ALA (-)). For each OSCC cell line, 100 μl of each concentration of cells of the 5-ALA groups was seeded onto fluorescence plates, and fluorescence intensity was measured at 60-min intervals for 240 min. Results are expressed as the ratio of fluorescence intensity in 5-ALA (+) to 5-ALA (-). As cells at the concentration of 106 cells/ml provided the clearest results, fluorescence intensities of all cell lines were measured using this concentration at 20-min intervals for 700 min using the same methods. Results: The 5-ALA (+) to (-) ratio increased in a cell concentration-dependent manner at 240 min;the ratio was highest with 106 cells/ml and lowest with 104 cells/ml. With 106 cells/ml in the 5-ALA (+) group, fluorescence intensity increased in a metabolic time-dependent manner;the increase was highest in HSC-2 cells, followed by HSC-4 cells, HSC-3 cells, Sa3 cells, and HOK. Fluorescence intensity was significantly enhanced after 40 min in HSC-2, HSC-3, and HSC-4 cells, after 60 min in Sa3 cells, and after 100 min in HOK compared to the 5-ALA (-) group (P < 0.05). Moreover, fluorescence intensity was significantly increased in OSCC cell lines compared to HOK after 40 min. Conclusion: Early detection of OSCC is possible by screening only microplate reader measurements of fluorescence intensity for PDD.

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.

STUDY OF ESTROGEN RECEPTOR AND PROGESTERONE RECEPTOR IN SQUAMOUS CELL CARCINOMA TISSUE OF ORAL MUCOSA

By means of the enzyme linked affinity histothemical method, 45 cases of squamous cell carcinoma(SCC) of the oral mucosa and 15 cases of the approximately normal oral mucosal tissue were detected for estrogen receptor(ER) and progesterone receptor(PR). The results indicated that In the SCC tissue of the oral mucosa there were 5 cases of ER+ and PR- and 32 cases of both ER+ and PR+. Thirty-seven cases, the summation of the above two items, were considered as receptor(+),therefore the rate of the receptor(+) being 82.22%. ER+ and PR+ were cd related to the sex and age of patients, the neck lymph nodes' metastasizing or not and affected parts of the tumor, while they were related to the differentiation degree of the tumor. The rate of receptor(+) decreased with the decrease of the differentiation degree of the tumor. By X2 test a remarkable difference between grade Ⅰand grade Ⅲ of SCC of the oral mucosa was shown. It is suggested that SCC of the oral mucosa may probobly be hormone dependent tumor. The authors consider that the SCC detection for ER and PR could not only be one of the indices of biologic characteristics for that tumor but also as bases of anti-hormone treatment.

An Analysis of the Potential Benefits of Metformin on Disease Recurrence in Oral and Oropharyngeal Squamous Cell Carcinoma

Objective: Diabetes mellitus type 2 has been associated with increased cancer risk and cancer related mortality. Metformin, one of the most widely used anti-diabetic medications, has been found to have important anticancer properties in addition to hypoglycemic effects. The effects of metformin on clinical outcomes in oral cavity (OC) and oropharyngeal (OP) squamous cell carcinoma (SCC) have not been thoroughly analyzed. The purpose of this study was to evaluate the effects of metformin use on cancer recurrence in diabetic patients with oral cavity and oropharyngeal squamous cell carcinoma. Design: Retrospective review. Setting: Academic tertiary medical center. Patients: Seventy-seven patients with diabetes mellitus type 2 and oral cavity or oropharyngeal squamous cell carcinoma were treated and followed at our tertiary academic institution and the Veterans Affairs Greater Los Angeles Healthcare System from 1998 to 2012. Main Outcome Measure: Cox proportional hazards models and Kaplan-Meier curves were constructed to determine if metformin has an effect on disease recurrence after primary cancer treatment. Results: Metformin does not appear to have a significant effect on disease recurrence in patients with OC/OP SCC and diabetes mellitus type 2 (p = 0.53). Even when including only patients with stage I or II disease, metformin still did not decrease recurrence (p = 0.60). Conclusion: Herein, our data suggest that metformin use does not significantly impact time until recurrence for diabetic patients with OC/OP SCC.