Expression In Oral Squamous Cell Carcinoma Research Articles

Immunohistochemical Analysis Revealed a Correlation between Musashi-2 and Cyclin-D1 Expression in Patients with Oral Squamous Cells Carcinoma.

Aim: Musashi 2 (MSI2), which is an RNA-binding protein, plays a fundamental role in the oncogenesis of several cancers. The aim of this study is to investigate the expression of MSI2 in Oral Squamous Cell Carcinoma (OSCC) and evaluate its correlation to clinic-pathological variables and prognosis. Materials and Methods: A bioinformatic analysis was performed on data downloaded from The Cancer Genome Atlas (TCGA) database. The MSI2 expression data were analysed for their correlation with clinic-pathological and prognostic features. In addition, an immmunohistochemical evaluation of MSI2 expression on 108 OSCC samples included in a tissue microarray and 13 healthy mucosae samples was performed. Results: 241 patients’ data from TCGA were included in the final analysis. No DNA mutations were detected for the MSI2 gene, but a hyper methylated condition of the gene emerged. MSI2 mRNA expression correlated with Grading (p = 0.009) and overall survival (p = 0.045), but not with disease free survival (p = 0.549). Males presented a higher MSI2 mRNA expression than females. The immunohistochemical evaluation revealed a weak expression of MSI2 in both OSCC samples and in healthy oral mucosae. In addition, MSI2 expression directly correlated with Cyclin-D1 expression (p = 0.022). However, no correlation has been detected with prognostic outcomes (overall and disease free survival). Conclusions: The role of MSI2 expression in OSCC seems to be not so closely correlated with prognosis, as in other human neoplasms. The correlation with Cyclin-D1 expression suggests an indirect role that MSI2 might have in the proliferation of OSCC cells, but further studies are needed to confirm such results.

Relationship among hypoxia, 18F-fluoromisonidazole positron emission tomography uptake, and tumor angiogenesis in oral squamous cell carcinoma

Objectives Hypoxia is a common feature of cancer and, thus, is a prognostic factor for many types of cancer. Clinically, the prognosis of cancer with low oxygenation level is poor, and there is strong evidence that hypoxia in the tumor microenvironment is related to tumor angiogenesis and malignant progression. 18F-fluoromisonidazole (18F-FMISO) has been used in clinical and preclinical studies to provide spatially resolved images for localizing and quantifying tissue hypoxia.18F-FMISO can detect tumor hypoxia noninvasively. Hypoxia-inducible factor (HIF-1) is a key player in the transcriptional response to low oxygen in many types of cancer. Most transcriptional responses to low oxygen (O2) are mediated by HIFs, which are highly conserved transcription factors that control the expression of various angiogenic, metabolic genes. 18F-FMISO imaging of hypoxia in head and neck cancer remains challenging. It is unclear whether 18F-FMISO positron emission tomography (PET) can identify tumor anigiogenesis and HIF-1α expression in oral squamous cell carcinoma (OSCC). We evaluated the relationship among 18F-FMISO PET uptake, HIF-1α expression, and tumor angiogenesis in OSCC. Study Design In this retrospective study, immunohistochemistry was performed for CD31 and HIF-1α on 40 OSCC specimens. Each patient was evaluated by both 18F-FMISO PET before surgery, and the tumor–muscle ratio (TMR) of 18F-FMISO PET were measured. The threshold for the hypoxic volume based on TMR was set at 1.25 (TMR ≥ 1.25: hypoxic tumor; and TMR Results 18F-FMISO uptake in the primary site of OSCC indicates a hypoxic environment with HIF-1α expression. The CD31-positive vessel area was increased in the hypoxic tumor compared with that in the nonhypoxic tumor. The tumor vessel in the hypoxic tumor was morphologically more irregular and tortuous than that in the nonhypoxic tumor. Conclusions We demonstrated a significant relationship between 18F-FMISO TMR and CD31 and HIF1α expression in OSCC. In the future, we will perform detailed research on the relationship between tumor angiogenesis and 18F-FMISO uptake.

EVALUATION OF MICRORNAS RELATED TO THE SONIC HEDGEHOG PATHWAY IN ORAL CANCER

The microRNAs (miRNAs) as biomarkers with clinical application in oral squamous cell carcinoma (OSCC) has been suggested in literature. These small noncoding RNA molecules can act as oncogenes or tumor suppressor molecules. Altered expression of miR-17, miR-214, and miR-324 was described and related to the sonic hedgehog (SHH) pathway in medulloblastomas. SHH is an important embryonic pathway associated with progression and poor prognosis in OSCC. A better comprehension about the miRNA activity will improve the knowledge about the SHH pathway in oral carcinogenesis. Objective: This study aims to evaluate the Gli1 (an important SHH component) and miR-17, miR-214, and miR-324 expression in OSCC. Study Design: Gli1 evaluation was performed by immunohistochemistry and miR-17, miR-214, and miR-314 expression was investigated using real time polymerase chain reaction in 20 OSCC samples. Results: Gli1 demonstrated a cytoplasmic and nuclear positivity mainly in the undifferentiated histologic grade. Hypoexpression of miR-324 and miR-214 was observed in 40% and 60% of OSCC samples, respectively. A higher expression of miR-17 was identified in 60% of these samples. Conclusion: A possible tumor suppressor and oncogenic profile of miR-324 and miR-17, respectively, as mentioned in medulloblastomas was observed. However, miR-214 did not demonstrate an oncogenic behavior on OSCC.

MSH2 EXPRESSION IN ORAL SQUAMOUS CELL CARCINOMA

Objective The objective of the present work was to evaluate the DNA repair gene MSH2 expression in oral squamous cell carcinoma (OSCC). Study Design The carcinoma group was composed of 32 OSCC samples and the control group by 15 samples of tissue borders of benign lesions removed from the oral cavity of patients equivalent in age, sex, and smoking habits to the patients of OSCC group. Gene expression was assessed by quantitative reverse transcription polymerase chain reaction (RT-qPCR). In addition, clinical data, such as age, amount of cigarettes per day, time of tobacco consumption, smoking history (pack-years), degree of nicotine dependence, risk of alcohol use, and neoplasm staging were evaluated. The groups were compared using the Student t test and the correlation of the expression levels and clinical data were explored using the Pearson correlation coefficient, with P Results It was observed higher prevalence of males, with a mean age in years ± SD of 57.44 ± 13.32. The MSH2 gene was downregulated (1.13 fold decrease) in the OSCC group compared to the control with significant results (P = .0380). There was no significant correlation between MSH2 expression and the clinical variables studied. Conclusions MSH2 expression in OSCC was reduced.

Overexpression of JAG2 is related to poor outcomes in oral squamous cell carcinoma.

ObjectivesJAG2 is one of Notch ligands, which recently appear to exert various carcinogenesis. In the present study, we aimed to unveil the relation of JAG2 expression and clinicopathological features in oral squamous cell carcinoma (OSCC).Materials and MethodsWe examined JAG2 expression in OSCC plus adjacent nontumorous epithelia in eight patients. Ninety‐one OSCC tissue specimens were immunohistochemically stained with specific antibodies to JAG2. The immunoreactivities of JAG2 were correlated with clinicopathological factors, including the prognosis of patients. Chi‐square test, Kaplan–Meier survival, and Cox proportional hazard analysis were used to determine the statistical value of JAG2 expression in OSCC.Results JAG2 mRNA expression was much expressed in OSCC tissues compared with adjacent tissue specimens in five of eight patients. JAG2 immunoreactivity was found at invasion front in 31 of 91 OSCC. JAG2 immunoreactivity was significantly associated with age, less than 50 years old of patients (P = .048). Kaplan–Meier analysis demonstrated that the patients with JAG2 immunoreactvty have a short overall survival. With the Cox proportional hazard regression mode, the independent factors predictive of poor overall survival included JAG2 immunoreactivity (P < .05).ConclusionsThe present findings suggest that JAG2 overexpression, especially at the cancer invasion front, has potential prognostic value.

MiR-1290 targets CCNG2 to promote the metastasis of oral squamous cell carcinoma.

MicroRNAs (miRNAs) have been demonstrated to be involved in the pathogenesis of various human cancers, including oral squamous cell carcinoma (OSCC). Here, we designed this study to explore the potential effect of miR-1290 on tumorigenesis of OSCC. The expressions of miR-1290 and cyclin G2 (CCNG2) in OSCC were observed by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Dual-Luciferase Reporter Assay was performed to confirm the relationship between miR-1290 and CCNG2. The functions of miR-1290 and CCNG2 were analyzed using transwell assay. The Western blot analysis was used to detect epithelial-mesenchymal transition (EMT). Upregulation of miR-1290 and downregulation of CCNG2 were identified in OSCC. And upregulation of miR-1290 was associated with clinicopathological characteristics and poor prognosis in OSCC patients. Moreover, the downregulation of miR-1290 inhibited cell metastasis and EMT in OSCC cells. Furthermore, CCNG2 was a direct target of miR-1290. Its expression was inversely regulated by miR-1290 in OSCC cells. At the same time, the suppressive effect of CCNG2 was observed in OSCC. Furthermore, overexpression of CCNG2 weakened the promoted effect of miR-1290 on cell metastasis in OSCC. MiR-1290 promoted cell metastasis and EMT, inhibiting CCNG2 expression in OSCC.

Targeting FAT1 Inhibits Carcinogenesis, Induces Oxidative Stress and Enhances Cisplatin Sensitivity through Deregulation of LRP5/WNT2/GSS Signaling Axis in Oral Squamous Cell Carcinoma.

FAT atypical cadherin 1 (FAT1) regulates cell-cell adhesion and extracellular matrix architecture, while acting as tumor suppressor or oncogene, context-dependently. Despite implication of FAT1 in several malignancies, its role in oral squamous cell carcinoma (OSCC) remains unclear. Herein, we document the driver-oncogene role of FAT1, and its mediation of cell-death evasion, proliferation, oncogenicity, and chemoresistance in OSCC. In-silica analyses indicate FAT1 mutations are frequent and drive head-neck SCC, with enhanced expression defining high-risk population and poor prognosis. We demonstrated aberrant FAT1 mRNA and protein expression in OSCC compared with non-cancer tissues, whereas loss-of-FAT1-function attenuates human primary SAS and metastatic HSC-3 OSCC cell viability, without affecting normal primary human gingival fibroblast cells. shFAT1 suppressed PCNA and upregulated BAX/BCL2 ratio in SAS and HSC-3 cells. Moreover, compared with wild-type cells, shFAT1 concomitantly impaired HSC-3 cell migration, invasion, and clonogenicity. Interestingly, while over-expressed FAT1 characterized cisplatin-resistance (CispR), shFAT1 synchronously re-sensitized CispR cells to cisplatin, enhanced glutathione (GSH)/GSH synthetase (GSS)-mediated oxidative stress and deregulated LRP5/WNT2 signaling. Concisely, FAT1 is an actionable driver-oncogene in OSCC and targeting FAT1 in patients with erstwhile cisplatin-resistant OSCC is therapeutically promising.

PDL-1 expression in oral squamous cell carcinoma and implications for treatment.

82 Background: PDL-1 expression has been shown in multiple tumours to be a key factor in treatment response and immunogenicity. In oral squamous cell carcinoma (OSCC), its role is controversial; the expression levels, prognostic significance and therapeutic relevance are unclear. This study was performed to determine the incidence of PDL-1 expression in OSCC, and to determine its correlation with demographic, clinical and pathological features, recurrence and survival. Methods: PDL1 expression levels were determined by immunohistochemistry (DAKO kit) on 64 samples of OSCC obtained during resection on tumour (T) and tumour infiltrating lymphocytes (TILs). Statistical analysis was performed for corelation with clinicopathological features and survival. We also analysed PD1/PDL1 expression on the mRNA-seq data from The Cancer Genome Atlas (TCGA) (n = 527) and Gene Expression Omnibus (GEO) (n = 61) for validation. Results: PDL1 expression of &lt; 1% was the most common for T (92%) and TILs (56%). Tumour PDL-1 expression &lt; 1% had higher lymphovascular invasion (LVI) (p = 0.044) and bone invasion (p = 0.010). TIL PDL-1 expression &lt; 1% was more common in patients &lt; 45 years (p = 0.023) with more local recurrences (p = 0.020). For TCGA data, overall survival (OS) in the young ( &lt; 45 years) was reduced in patients with low ( &lt; 1%) PD1 expression (p = 0.010) while GEO data showed that older patients ( &gt; 45 years) had a significantly higher PD1 expression level (p = 0.044). Conclusions: PDL1 expression in OSCC was low. Low TIL PDL1 expression was more common in patients with age &lt; 45 years, with a higher chance of local recurrence. Genomic data also validated a potential link between PD1 expression and age. On the tumour, PD1 expression may be an important prognosticator, while on TILs, PDL1 is likely more relevant. Moreover PDL1 expression on the tumour is likely to be heterogeneous, so TIL PDL1 expression may be more representative of the tumour microenvironment and a better prognostic marker.

USP13 serves as a tumor suppressor via the PTEN/AKT pathway in oral squamous cell carcinoma.

Background: Recent studies have shown that USP13 a deubiquitinase, serves as an important regulator of tumorigenesis. However, the biological role of USP13 in oral squamous cell carcinoma (OSCC) remains enigmatic.Materials and methods: We examined USP13 expression in OSCC and adjacent normal tissues by immunohistochemical staining. The biological functions of USP13 in OSCC cells and the possible underlying mechanisms were investigated.Results: In this study, we showed that USP13 expression was frequently reduced in human OSCC specimens and that the reduction was correlated with the clinical stage. Functional studies demonstrated that overexpression of USP13 suppressed OSCC cell proliferation, glucose uptake and lactate production in vitro and inhibited tumor growth in vivo. Furthermore, USP13 overexpression induced phosphatase and tensin homolog deleted on chromosome 10 (PTEN) expression and repressed the activation of AKT as well as the expression of the downstream effectors glucose transporter-1 (GLUT1) and hexokinase-2 (HK2). Overexpression of PTEN reversed the USP13-knockdown-induced glucose uptake, lactate production, AKT activation, and expression of GLUT1 and HK2.Conclusion: Our findings suggest that USP13 serves as a tumor suppressor by regulating the PTEN/AKT signaling pathway in OSCC cells, improving our understanding of OSCC progression and providing a clue for the development of a novel cancer therapy.

MUC1 gene silencing inhibits proliferation, invasion, and migration while promoting apoptosis of oral squamous cell carcinoma cells.

The aim of the present study is to investigate the role of RNA interference in the inhibition of MUC1 gene expression in occurrence and metastasis of oral squamous cell carcinoma (OSCC) and its in-depth mechanisms. The OSCC and normal oral mucosa tissues, as well as normal oral epithelial cell line HOK and OSCC cell line SCC-4, Cal-27, TSCCA, Tca8113 were obtained to detect the expression of MUC1. Slug expression in OSCC and normal oral mucosa tissues was also determined. The OSCC cells were grouped to investigate the role of MUC1 gene silencing on proliferation, DNA replication, cell cycle distribution, apoptosis, colony formation ability, epithelial-mesenchymal transition (EMT), invasion, and migration of OSCC cells. We first found higher positive rate of MUC1 and Slug expression in OSCC tissues. Next, it was determined that higher expression of MUC1 was found in OSCC tissues and cells. Furthermore, silencing of MUC1 declined Slug expression, inhibited the proliferation, DNA replication, cell cycle progression, and EMT while inducing apoptosis of OSCC cells. Our study suggests that overexpression of MUC1 is found in OSCC, and MUC1 gene silencing could inhibit the proliferation, invasion, and migration while inducing apoptosis of OSCC cells.

Focal Adhesion Kinase (FAK) Overexpression and Phosphorylation in Oral Squamous Cell Carcinoma and their Clinicopathological Significance.

Focal adhesion kinase (FAK) is involved in progression of various cancers, and FAK overexpression has been associated with cancer invasion and metastasis. However, the involvement of FAK expression in the clinicopathological malignancy of oral squamous cell carcinoma (OSCC) remains unknown. In addition, there is no consensus regarding the role of p16 expression in OSCC. In this study, the immunohistochemically measured expression of FAK, phosphorylated FAK (FAKpY397) and p16 expressions and their associations with clinicopathological features and 5-year survival rates were examined in surgical samples from 70 patients with primary OSCC. FAK and FAKpY397 were expressed at high levels in 42 cases (60.0%) and 34 cases (48.6%), respectively, and 9 cases (12.9%) were positive for p16. FAK expression was significantly correlated with local recurrence, subsequent metastasis, and the mode of invasion. FAKpY397 expression was significantly correlated with both N classification and the mode of invasion. p16 expression was significantly correlated with clinical stage only. Patients having high expression of FAK, FAKpY397, or both showed significantly worse prognosis, but p16 expression showed no significant relation to prognosis. The results suggested that overexpression and phosphorylation of FAK in OSCC may affect cancer progression, such as local invasion and lymph node metastasis, and thereby contribute to life prognosis.

Assessing the Expression of Aquaporin 3 Antigen-Recognition Sites in Oral Squamous Cell Carcinoma.

Aquaporin 3 (AQP3) serves as a water and glycerol transporter facilitating epithelial cell hydration. Recently, the involvement of AQP3 in cancers has been reported. However, the immunohistochemical expression of AQP3 in carcinomas remains controversial. We hypothesized that differences in aquaporin 3 antigen recognition (AQP3 AR) may influence their expressions. Thus, our study aimed to assess the immunostaining patterns of 3 AQP3 AR sites in oral squamous cell carcinoma (OSCC) and to compare the adjacent areas of high-grade epithelial dysplasia (HG-ED) and normal oral mucosa (NOM). The study group included formalin-fixed OSCC samples (n=51) with adjacent regions of HG-ED (n=12) and NOM (n=51). The tissues were stained with anti-AQP3 antibodies (AR sites at amino acid (AA) 250-C terminus, AA180-228, and N terminus AA1-80) by immunohistochemistry. Our results showed that strong membranous immunostaining was observed for AQP3 AR sites at the AA250-C terminus and AA180-228 in all the samples for NOM and weak AQP3 immunostaining for both the AR sites in all the 12 samples for HG-ED. The invasive front of OSCC samples showed that AQP3 AR at the AA250-C terminus decreased in 42/51 samples (82.4%) and AA180-228 in 47/51 samples (92.2%). Conversely, in the AQP3 AR site at N terminus AA1-80, all samples of the NOM showed negative or slightly positive staining in the cytoplasm of the lower layers. AQP3 expression was increased in 12/12 cases (100%) and 46/51 cases (90.2%) in the HG-ED and invasive front of OSCC, respectively. AQP3 may be used as a biomarker for detecting malignant transformations. AQP3 AR site differences influence their immunohistochemical expression in OSCC.

Overexpression of Epstein-Barr virus-encoded latent membrane protein-1 (LMP-1) in oral squamous cell carcinoma

BackgroundAs oral cavity is the main location of Epstein-Barr virus (EBV) latency and shedding, and as EBV-encoded latent membrane protein-1 (LMP-1) has a crucial role in cell transformation, association between EBV infection, LMP-1 expression and oral malignancy is of interest. Although EBV DNA has been detected in oral squamous cell carcinoma (OSCC), studies on LMP-1 expression in OSCC and oral potentially malignant disorders are scarce and still controversial. This study aimed to evaluate the expression of LMP-1 in OSCC and oral leukoplakia (OL).MethodsBiopsy specimens of 36 OSCC, 69 OL with and without dysplasia and 10 normal oral mucosa were assessed for the expression of LMP-1 using immunohistochemistry. In each case, at least 1000 cells were counted. Cells with staining were considered positive, classified by location as nuclear, cytoplasmic and nuclear plus cytoplasmic staining. Percentage of positive cells at different locations and of total positive cells were determined. For statistical analysis, SPSS version 21 was used. Statistical significance was considered at p < 0.05.ResultsLMP-1 was expressed in all studied specimens. In terms of percentage of total positive cells, LMP-1 expression was higher from normal mucosa (26.36%), OL without dysplasia (28.03%), OL with dysplasia (34.15%), to the significantly highest, (59.67%) in OSCC. In addition, cells with nuclear staining alone, cytoplasmic staining alone and cells with nuclear plus cytoplasmic staining were significantly higher in OSCC compared to those of normal mucosa, OL with and without dysplasia.ConclusionsLMP-1 was overexpressed in OSCC. Our analysis on subcellular localization of LMP-1 in OSCC revealed prominent distinguished pattern, cytoplasmic distribution. Further studies in cell lines and animals are required to clarify the association between this EBV-encoded proteins and oral carcinogenesis.

Cyclooxygenase and CD147 expression in oral squamous cell carcinoma patient samples and cell lines

In oral squamous cell carcinoma (OSCC), cyclooxygenases (COX-1 and COX-2) contribute to inflammation, and cluster of differentiation factor 147 (CD147) contributes to invasiveness, but their relationship has not been previously examined within a cohort of patients with OSCC or OSCC cell lines. COX-2 and CD147 expression was determined by using immunohistochemistry on 39 surgical biopsy specimens of OSCC. Expression in tumor cells, stroma, and adjacent oral epithelium was characterized by using a visual grading system. COX-1, COX-2, and CD147 expression was determined in vitro by using OSCC cell lines (SCC25, BHY, and HN) and reverse transcriptase-quantitative polymerase chain reaction. Secretion of prostagladin E2 (PGE2) from OSCC cell lines was determined by using PGE2 enzyme-linked immunosorbent assay. Biopsy specimens showed higher COX-2 expression in tumor cells compared with stroma and adjacent epithelium (P < .05). There was no difference in CD147 expression among the tumor cells, stroma, and adjacent epithelium. In OSCC cell lines, there was a trend for COX-2 and CD147 gene expression to be coordinated. Interestingly, PGE2 secretion was more closely related to COX-1 expression than to COX-2 expression. COX-1, COX-2, and CD147 appear to be independently regulated in OSCC, potentially representing 2 therapeutic targets for future investigation. COX-1 expression in OSCC deserves further study because it may be an important determinant of PGE2 secretion from OSCC cells.

Reduced ribosomal RNA expression and unchanged ribosomal DNA promoter methylation in oral squamous cell carcinoma.

BackgroundRibosomal RNA (rRNA) consists of four non‐coding RNAs, the 28S, 5.8S, 18S, and 5S rRNA. Abnormal expression of rRNA has been found in multiple tumors, and the methylation of rDNA promoter may affect rRNA expression as an epigenetic regulatory mechanism. Oral squamous cell carcinoma (OSCC) is a kind of aggressive tumors which occurs in multiple sites in oral cavity. rRNA expression and the methylation of rDNA promoter in modulating rRNA expression in OSCC maintain unclear. This study aims to investigate the rRNA expression, the methylation status within rDNA promoter, and the underlying mechanism of methylation in regulating rRNA expression in OSCC.MethodsTwelve primary OSCC and matched normal tissue samples were collected from patients with OSCC. Quantitative real‐time PCR was used to evaluate the rRNA level. HpaII/MspI digestion and bisulfite sequencing were used to investigate the methylation status of rDNA promoter.ResultsRibosomal RNA levels were suppressed in OSCC as compared with matched normal tissues. HpaII/MspI digestion and bisulfite sequencing showed no significant differences for the methylation of rDNA promoter between the tumor and matched normal tissues.ConclusionThe methylation in rDNA promoter could not explain for the suppressed rRNA expression in OSCC tissues.

Relative Expression of OCT4, SOX2 and NANOG in Oral Squamous Cell Carcinoma Versus Adjacent Non- Tumor Tissue.

Objective:Oral squamous cell carcinoma (OSCC) accounts for over 90% of oral neoplasms. Finding molecular markers for predicting prognosis is a high priority. The core transcription factors, OCT4, SOX2, and NANOG that regulate embryonic stem cell pluripotency have been implicated in progression of various malignancies. The predictive value of these markers and their role in the development of OSCC is still controversial. In this study, we therefore evaluated their expression in OSCCs and adjacent non-tumor tissue. Methods:A total of 60 frozen tumor and adjacent non-tumor tissue samples from 30 patients with OSCC were examined using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Clinical and pathological data of patients including tumor stage, lymph node metastasis and tumor grade were also recorded. Results:Expression of SOX2 was significantly higher in adjacent non-tumor as compared to tumor tissue (P=0.04). No statistically significant differences were found for expression of OCT4 (P=0.50) and NANOG (P=0.68). Also, there was no significant association between expression of OCT4, SOX2, and NANOG and clinical or pathological data (P>0.05), although slightly higher values were noted in patients without lymph node metastasis. Conclusion:Based on the present data, decreased expression of SOX2 is correlated with carcinogenesis in the oral cavity and development of OSCC.

Upregulated LOX and increased collagen content associated with aggressive clinicopathological features and unfavorable outcome in oral squamous cell carcinoma.

Collagen is a core protein that maintains the homeostasis of the extracellular matrix (ECM), and its dysregulation in human cancers has attracted increasing attention. In tumors, increased lysyl oxidase (LOX)-catalyzed collagen cross-linking plays a critical role in collagen dysregulation. However, the expression patterns of LOX and collagen and their clinicopathological significance in oral squamous cell carcinoma (OSCC) have not been well established. The LOX mRNA expression in OSCC was measured by RT-PCR and bioinformatics analysis. LOX protein expression and total collagen content were identified by immunohistochemistry or Masson's trichrome staining in a retrospective cohort of primary OSCC samples, respectively. Moreover, the associations between LOX and collagen expression and various clinicopathological parameters or patient survival were assessed. LOX mRNA was overexpressed in OSCC samples. Higher expression of LOX, collagen content or co-overexpression of LOX and collagen was significantly associated with aggressive clinicopathological features. Importantly, aberrant expression of LOX, collagen content, or both were markedly correlated with decreased overall and disease-free survival (P < 0.05). Moreover, univariate and multivariate Cox models analyses indicated that LOX, collagen content or their combination could serve as an independent prognostic predictor for OSCC patients. ROC analysis further revealed that the combination of LOX and collagen was superior to parameter alone as a prognostic predictor. Our findings reveal that elevated LOX and collagen content significantly corelate with aggressiveness and worse prognosis in OSCC.

PDL-1 expression in oral squamous cell carcinoma and implications for treatment.

e17527 Background: PDL-1 expression has been shown in multiple tumours to be a key factor in treatment response and immunogenicity. In oral squamous cell carcinoma (OSCC), its role is controversial; the expression levels, prognostic significance and therapeutic relevance are unclear. This study was performed to determine the incidence of PDL-1 expression in OSCC, and to determine its correlation with demographic, clinical and pathological features, recurrence and survival. Methods: PDL-1 IHC (Dako kit) was determined on 64 samples of OSCC obtained during curative intent resection. PDL-1 expression levels were determined in tumour (T) and tumour infiltrating lymphocytes (TILs). Statistical analysis was performed. Results were validated on the mRNA-seq data from the Cancer Genome Atlas (TCGA) for head and neck squamous cell carcinoma (HNSCC). Results: 64 patients were included in the final analysis with a mean age of 54 years. &lt; 1% expression was the most common for T (92%) and TILs (56%). Tumour PDL-1 expression &lt; 1% had higher risk of lymphovascular invasion (LVI) (p = 0.044) and bone invasion (p = 0.010). TIL PDL-1 expression &lt; 1% was more common in patients ≤45 years (p = 0.023) with higher chances of local recurrence (p = 0.020) and reduced local recurrence free survival (p = 0.047). For the TCGA data, low ( &lt; 1%) PDL-1 expression was associated with a significant reduction in OS and DFS in the young (≤45 years) (p = 0.0078 and 0.0089 respectively), but not for older patients ( &gt; 45 years) (p = 0.21 and 0.88 respectively). Conclusions: PDL-1 expression in OSCC was low. TIL PDL-1 expression &lt; 1% was more common in those ≤45 years, and associated with a higher chance of local recurrence and poorer survival. The role of PDL-1 expression in prognosis of OSCC is controversial, with our data being the first to correlate low PDL-1 expression and poorer outcomes with younger patients. These results were validated by the TCGA data for HNSCC across multiple subsites. Further study is required to determine if this pathway plays a significant role in local control and survival.

Immunohistochemical assessment of growth factor signaling molecules: MAPK, Akt, and STAT3 pathways in oral epithelial precursor lesions and squamous cell carcinoma.

Several growth factors and their receptors, such as epidermal growth factor receptor, have been studied as prognostic biomarkers for many epithelial malignancies. The signal transduction cascade of those receptors includes RAS/RAF/ERK, PI3K/Akt/mTOR, and STAT3 pathways. The aim of this study was to investigate the expression levels of several key proteins of those pathways in patients with oral squamous cell carcinoma (OSCC) and oral epithelial precursor lesions (OEPLs), and to correlate the expressions of these proteins with clinicopathologic features and prognosis. Fifteen leukoplakia (LP), 15 low-grade epithelial dysplasia, 15 high-grade epithelial dysplasia (HD), and 132 OSCC specimens were immunohistochemically examined for KRAS, HRAS, NRAS, BRAF, pERK1/2, pAkt, pmTOR, and pSTAT3 expression. Immunoreactivity for these molecules predominantly occurred in regions OEPL basal to prickle layers and in most OSCC cells. KRAS and NRAS expression was significantly lower in OSCC than in OEPLs, while pAkt and pmTOR showed higher expression in OSCC than in OEPLs. pERK1/2 expression was significantly higher in HD than in LP. In OSCC, KRAS and NRAS immunoreactivity was significantly higher in advanced age and male gender. In addition, higher immunoreactivity was shown in pERK1/2 in female gender and advanced TNM stage, pAkt in advanced T classification and cases without postoperative metastasis, pmTOR in advanced mode of invasion, and pSTAT3 in invasion depth. Correlations between these markers and clinicopathological variables were also noted. MAPK, Akt, and STAT3 pathways might play diverse roles in oral carcinogenesis.

Anti-alpha-enolase T cell response in oral squamous cell carcinoma

Abstract In Taiwan, oral cancer ranks as the 6th highest incidence of cancer in general population. Characterized by high metastatic potency, oral squamous cell carcinoma (OSCC) is the most common type of oral cancer. Alpha-enolase (α-enolase) is a glycolytic enzyme expressed in most tissues. Many researches have pointed out the over-expression of α-enolase in various cancer type. Its role as glycolytic enzyme and plasminogen receptor were reported to promote cancer invasion, proliferation, and metastasis. Our works focused on the relationship between α-enolase and OSCC. We found the increased α-enolase expression in OSCC and were able to detect anti-α-enolase antibodies in serum of some OSCC patients. These results revealed a non-negligible influence of α-enolase in OSCC. Next, we spliced α-enolase from whole protein into peptide pool and tested T cell response upon its stimulation. Both CD8+ T cells and CD4+ T cells from peripheral blood mononuclear cells (PBMCs) and tumor infiltrating lymphocytes (TILs) were able to detect the cytokine production, like interferon gamma (IFN-γ) or tumor necrosis factor (TNF-α), and as well as the expression of activation marker like CD107a. Taken together, our works indicated that α-enolase is a potential antigen that may be involved in anti-tumor response in OSCC.