Oral Squamous Cell Carcinoma Tumor Tissues Research Articles

Long non-coding RNA LINC01137 contributes to oral squamous cell carcinoma development and is negatively regulated by miR-22-3p.

Long noncoding RNAs (lncRNAs) are emerging as key regulators in cancer initiation and progression. LINC01137 is a recently identified lncRNA of which the functional role in the development of oral squamous cell carcinoma (OSCC) has not been determined yet. We analyzed the expression of LINC01137 using a microarray-based OSCC gene expression dataset (GSE31056), and validated the results obtained using RT-qPCR in 26 pairs of primary OSCC tumor tissues and adjacent non-tumor tissues. The proliferative and invasive effects of LINC01137 on OSCC cells were determined using CCK-8, colony formation and transwell assays, respectively. Targeted binding between miR-22-3p and LINC01137 was verified using a dual luciferase reporter assay. We found that LINC01137 was significantly upregulated in primary OSCCs. LINC01137 knockdown inhibited OSCC cell proliferation, migration and invasion, whereas LINC01137 overexpression induced opposite effects. LINC01137 upregulation along with p53 inhibition enhanced the malignant transformation of oral cells. In addition, we found that miR-22-3p can directly target LINC01137 through interaction with a putative miR-22-3p-binding site present within the LINC01137 sequence. A significant negative correlation was observed between LINC01137 and miR-22-3p expression in primary OSCC specimens. Exogenous overexpression of miR-22-3p markedly reduced the endogenous expression level of LINC01137 in OSCC cells. Additional functional assays showed that miR-22-3p overexpression enhanced the inhibitory effect of siRNA-mediated LINC01137 silencing on OSCC cell proliferation, migration and invasion, whereas miR-22-3p inhibition had the opposite effect. Our results indicate that LINC01137 functions as an oncogenic lncRNA in OSCC. miR-22-3p can directly target LINC01137 and negatively regulate its expression and function.

Relationship Between mir15b and Sal-Like Protein 4 and Biological Behavior of Oral Squamous Cell Carcinoma

miR15b and SALL4 are involved in a variety of tumor progression. The roles of miR15b and SALL4 in oral squamous cell carcinoma (OSCC) remains unclear. The tumors and normal mucosa of OSCC patients were collected to detect miR15b and SALL4 level by Real-time PCR and analyze their correlation with OSCC clinicopathological features. Oral cancer Tca8113 cells were separated into control group; miR15b mimics group and miR15b inhibitor group followed by analysis of SALL4 expression, cell survival by MTT assay; cell invasion by Transwell chamber assay, as well as expression of N-cadherin and Vimentin and correlated with TNM stage, tumor volume and metastasis, and positively with differentiation TGF-β by Western blot. miR15b expression was decreased and SALL4 expression was increased in OSCC tumor tissues. miR15b was negatively degree (P < 0.05), whereas, opposite correlation of SALL4 with the above parameters was found (P < 0.05). miR15b and SALL4 were negatively correlated. MiR15b mimics significantly up-regulated MiR15b, decreased SALL4 expression, inhibited Tca8113 cell proliferation and invasion, as well as reduced N-cadherin, Vimentin and TGF-βexpression (P < 0.05). Opposite results were found in MiR15b inhibitor group. MiR15b expression is decreased and SALL 4 is increased in OSCC tumor tissues. MiR15b and SALL4 is closely related to OSCC clinicopathological features. MiR15b regulates the expression of EMT-related genes and TGF-β, thereby altering the proliferation and invasion of OSCC cells.

Knockdown of RhoC Inhibits Oral Squamous Cell Carcinoma Cell Invasion and Metastasis via Regulation of HMGA2.

Ras homolog family member C (RhoC) is an important component of intracellular signal transduction and its overexpression has been reported to be involved in regulating tumor proliferation, invasion, and metastasis in various malignant tumors. However, its role and underlying mechanism in oral squamous cell carcinoma (OSCC) still remain obscure. In our study, RhoC expression, its relation with clinical stages, and survival rate in OSCC were analyzed using datasets from The Cancer Genome Atlas (TCGA). Next, a RhoC knockdown cell model was established in vitro, and the effects of RhoC knockdown in OSCC cells were detected by the MTT assay, colony formation assay, transwell invasion assay, scratch assay, and F-actin phalloidin staining. An in vivo tongue-xenografted nude mouse model was established to measure the effects of knockdown of RhoC on tumor cell growth and lymph node metastasis. A mechanism study was conducted by real-time PCR and immunocytochemistry. The results of TCGA analysis showed that RhoC was overexpressed in OSCC tumor tissues. In vitro assays indicated that knockdown of RhoC did not have much effect on OSCC cell growth but significantly suppressed cell colony formation, invasion, and migration abilities, and F-actin polymerization was also reduced. The tongue-xenografted in vivo model demonstrated that knockdown of RhoC suppressed OSCC cell growth and inhibited metastasis to the superficial cervical lymph nodes. Further mechanism studies showed that knockdown of RhoC downregulated HMGA2 expression, and HMGA2 expression was highly correlated with RhoC expression in OSCC tumor tissues via the analysis of TCGA datasets. Overall, our study showed that knockdown of RhoC inhibited OSCC cells invasion and migration in vitro and OSCC cell growth and lymph node metastasis in vivo. Moreover, the potential mechanisms involved in these activities may be related to the regulation of HMGA2 expression. The RhoC gene could serve as a promising therapeutic target for OSCCs in the future.

Overproduced CPSF4 Promotes Cell Proliferation and Invasion via PI3K-AKT Signaling Pathway in Oral Squamous Cell Carcinoma

Invasion and metastasis are major challenges in the treatment of oral cancer. We hypothesize that cleavage and polyadenylation specific factor 4 (CPSF4), a key mediator of cell growth and metastasis in several types of cancers, contributes to oral squamous cell carcinoma (OSCC) pathogenesis. The expression and production of CPSF4 in OSCC cell lines and tumor tissues were assessed by RT-PCR and western blot, respectively. The relationships between CPSF4 production and OSCC clinicopathological features were analyzed using immunohistochemistry. The effects of CPSF4 on viability, proliferation, migration, invasion, cell cycle distribution, and apoptosis of OSCC cells were measured by MTS assay, colony formation assay, wound-healing, transwell invasion assay, flow cytometry, and cell apoptosis assay, respectively. Western blot analysis was used to assess alteration of PI3K-AKT pathway member levels in cell lines transfected with CPSF4 siRNA. Mice xenograft models were used to determine the effect of CPSF4 on OSCC tumor growth invivo. CPSF4 was highly expressed in OSCC cell lines and tumor tissues compared with adjacent normal oral tissues. High CPSF4 expression was strongly correlated with vascular invasion (P=.004), distant metastasis (P=.001), and TNM stages (P=.001). Moreover, reduction of CPSF4 levels contributed to the inhibition of cell viability, proliferation, invasion and migration, and the induction of apoptosis inOSCC cell lines. Reduction of CPSF4 levels results in OSCC cell cycle arrest in G1 phase by targeting c-Myc. CPSF4 contributed to proliferation inhibition via PI3K-AKT signaling pathway. Reduction of CPSF4 levels inhibits OSCC tumor growth invivo. Our results suggest that CPSF4 supports OSCC invasion and metastasis and may be a promising therapeutic target for OSCC.

Long noncoding RNA PVT1 promotes tumor cell proliferation, invasion, migration and inhibits apoptosis in oral squamous cell carcinoma by regulating miR‑150‑5p/GLUT‑1.

Oral squamous cell carcinoma (OSCC) is a cancer with high morbidity and mortality. Research has demonstrated that long non-coding RNAs (lncRNAs) are critical for tumor initiation and development. In the present study, we aimed to ascertain the functions and potential mechanisms of lncRNA plasmacytoma variant translocation 1 (PVT1) in OSCC. Firstly, we found that the expression of PVT1 was increased in human OSCC tumor tissues and it was related to reduced survival of the patients. Furthermore, miR-150-5p expression was downregulated in OSCC tumor tissues and it was negatively related with PVT1. Moreover, GLUT-1 protein expression was upregulated in human OSCC tumor tissues. In addition, cell proliferation capacity was measured by CCK-8 assay and cell invasion and migration were measured by Transwell assay. PVT1 overexpression promoted cell proliferation, invasion and migration, while these effects were abrogated by PVT1 downregulation. In addition, luciferase gene reporter assay verified the miR-150-5p directly binds with PVT1, which regulates the biological functions of OSCC. Additionally, luciferase gene reporter assay confirmed that GLUT-1 was a target for miR-150-5p. The promotion of cell proliferation, invasion and migration in LV-PVT1-transfected cells was eliminated following miR-150-5p overexpression. Finally, in vivo nude mouse xenograft model further verified that PVT1 knockdown inhibited tumor growth, formation, invasion and migration. According to the results, PVT1 is increased in human OSCC tumor tissues, and is related to the poor prognosis of human OSCC patients. We uncovered a previously unappreciated PVT1/miR-150-5p/GLUT-1 signaling axis that promotes cell proliferation, invasion, migration and inhibits apoptosis in OSCC cell lines and in vivo, which suggests that this axis could be a target for the treatment of OSCC.

KRT84 is a potential tumor suppressor and good prognosis signature of oral squamous cell carcinoma.

Aims: Oral squamous cell carcinoma (OSCC) is a common oral cancer; however, current therapeutic approaches still show limited efficacy. Our research aims to explore effective biomarkers related to OSCC.Main methods: Gene expression profiles of paired OSCC tumor and paracancerous samples from The Cancer Genome Atlas (TCGA) were analyzed. mRNA and protein levels of KRT84 in OSCC cell line HSC-3 were measured by real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot. KRT84 protein levels in OSCC tumor samples of different stages were determined by immunohistochemistry. Overall survival (OS) of OSCC samples was evaluated and association of multiple factors with OS was assessed.Key findings: Compared with paracancerous samples, 4642 DEGs were identified in OSCC tumor samples. Among them, KRT84 expression level in OSCC tumor tissues was obviously decreased, which was validated in HSC-3 cells. KRT84 expression level showed decreasing tendency with the increase of tumor grade and stage. Patients with low KRT84 expression level had inferior OS independently of multiple factors. Besides, antigen processing and presentation pathway were significantly activated in OSCC samples with high KRT84 expression. Elevated KRT84 mRNA as well as protein levels were confirmed by RT-qPCR and Western blot in OSCC and normal cell lines, and immunohistochemistry in OSCC tumor and paracancerous tissues.Significance: Our study suggests KRT84 as a tumor suppressor and good prognostic indicator for OSCC, which might be significant for OSCC diagnosis and treatment.

Long non-coding RNA RBM5-AS1 promotes the aggressive behaviors of oral squamous cell carcinoma by regulation of miR-1285-3p/YAP1 axis

The human genome encodes far more long non-coding RNA (lncRNA) genes than protein coding genes. However, the function of majority of the lncRNAs is poorly understood. Numerous lncRNAs were aberrantly expressed in various cancers and found to be associated with development and progression of cancer. Little is known about the role of lncRNAs in oral squamous cell carcinoma (OSCC). In this study, we identified lncRNA RBM5-AS1 to be highly expressed in OSCC tumor tissues and cancer cell lines. RBM5-AS1 promotes the proliferation, migration, and invasion of OSCC cells in vitro. We also found that RBM5-AS1 regulates the level of miR-1285-3p as a competitive endogenous RNA (ceRNA), therefore regulate the expression level of an oncogene-YAP1, a target of miR-1285-3p. The information obtained in this study is valuable for understanding the regulatory mechanism of lncRNA in the development of OSCC and for developing new strategies for the diagnosis and treatment of OSCC.

MTFP1 overexpression promotes the growth of oral squamous cell carcinoma by inducing ROS production.

Mitochondrial fission process 1 (MTFP1) is a novel nuclear-encoded protein that promotes mitochondrial fission. Increasing lines of evidence indicate that increased mitochondrial fission is involved in carcinogenesis and tumor progression. However, the expression and biological effects of MTFP1 in cancer development is still unclear, especially in oral squamous cell carcinoma (OSCC). In this study, we first evaluated the expression of MTFP1 in 12-paired OSCC tumor and peritumor tissues. We then explored the effects of MTFP1 knockdown or overexpression on cell growth by cell proliferation, colony formation, cell cycle, and cell apoptosis assays. Furthermore, the mechanisms by which MTFP1 promoted OSCC cell growth were explored. Our results showed that MTFP1 is frequently overexpressed in OSCC tissues. Functional experiments revealed that MTFP1 promoted the growth of OSCC cells by inducing the progression of cell cycle and suppressing cell apoptosis. Mechanistically, MTFP1 overexpression-mediated mitochondrial fragmentation and subsequent ROS production was found to be involved in the promotion of OSCC cell growth. Collectively, our study demonstrates that MTFP1 plays a critical oncogenic role in OSCC carcinogenesis, which may serve as a potential therapeutic target in the treatment of this malignance.

Increased LGALS3BP promotes proliferation and migration of oral squamous cell carcinoma via PI3K/AKT pathway

Previous studies showed that lectin galactoside-binding soluble 3 binding protein (LGALS3BP) is an important participant in tumor progression. However, its prognostic value and functional mechanism in oral squamous cell carcinoma (OSCC) are still unclear. In this study, we analyzed LGALS3BP expression in OSCC tissues via Oncomine databases and immunohistochemical staining. LGALS3BP was significantly up-regulated in OSCC tumor tissues. IHC analysis showed that LGALS3BP was predominantly expressed in tumor cells and correlated with poor clinical characteristics. In addition, high LGALS3BP expression predicted poor clinical outcomes and multivariate analysis revealed that LGALS3BP expression was as an independent prognostic factor for OS, DFS and RFS (p < .0001, p = .002, p = .002). Mechanically, LGALS3BP regulated OSCC proliferation and migration via PI3K/AKT pathways, which was abrogated by PI3K inhibitor LY294002 in a dose-dependent manner. Our results suggested that LGALS3BP could be served as a novel independent prognostic factor as well as a potential therapeutic target for OSCC treatment.

LncRNA LACAT1 promotes proliferation of oral squamous cell carcinoma cells by inhibiting microRNA-4301.

To investigate the expression of lncRNA LACAT1 in oral squamous cell carcinoma (OSCC) tissues, and to further investigate its potential mechanism in OSCC as well as its relationship with clinicopathology and prognosis. Quantitative Real-time polymerase chain reaction (qRT-PCR) was used to analyze LACAT1 level in 78 pairs of OSCC tumor tissues and adjacent tissues, and the interplay between LACAT1 level and OSCC clinical indices along with patient's prognosis was analyzed. Further, the expression level of LACAT1 in OSCC cell line was verified by qRT-PCR. In addition, after LACAT1 knockdown model was constructed using lentivirus and transfected into OSCC cell lines, cell cloning assay and flow cytometry were used to analyze the impact of LACAT1 on biological functions of OSCC cells, and finally its association with microRNA-4301 was explored. In this experiment, qRT-PCR results revealed that LACAT1 level in OSCC tumor tissue specimens was significantly higher than that in paracancerous tissues. In addition, the pathology stage in patients with higher level of LACAT1 was also higher while the overall survival rate was lower. Compared with sh-NC group, the cell proliferation ability of sh-LACAT1 group was significantly decreased while cell apoptosis was oppositely increased. QRT-PCR results showed that microRNA-4301 level was significantly elevated in cells of sh-LACAT1 group, suggesting that the expression of above two molecules was negatively correlated. Meanwhile, cell reverse experiment also demonstrated that LACAT1 and microRNA-4301 can be mutually regulated, and thereby promote the malignant progression of OSCC. The LACAT1 level was found significantly increased in OSCC tissues and cells, which resulted in an advanced OSCC pathological stage and a poor prognosis of patients. In addition, it was found that LACAT1 may promote the malignant progression of OSCC by modulating microRNA-4301 activity.

CircRNA_0109291 regulates cell growth and migration in oral squamous cell carcinoma and its clinical significance.

Objective(s):Circular RNAs (circRNAs), a new class of non-coding RNAs, have emerged as important regulators during tumorigenesis. However, the functions of circRNAs have not been completely clarified in the progression of cancers. In our study, a novel circRNA hsa_circ_0109291 was investigated in oral squamous cell carcinoma (OSCC) tissues and cell lines. Materials and Methods:The expression profile of circRNAs in OSCC tumor tissues was performed by high-throughput sequencing. The CCK-8 wound healing and apoptosis assay were measured in OSCC cell lines after transfection with si-0109291 or si-NC. Results:We discovered that hsa_circ_0109291 was significantly increased in OSCC tissues and cell lines compared with their corresponding control group. Knockdown of hsa_circ_0109291 inhibited proliferation and migration of OSCC cell lines in vitro. In addition, inhibition of hsa_circ_0109291 dramatically induced apoptosis of OSCC cells. We further found that high hsa_circ_0109291 levels in OSCC patients resulted in a poorer prognosis than in patients with low hsa_circ_0109291 levels. Conclusion:These findings indicated that hsa_circ_0109291 correlated with the progression of OSCC and might be a new therapeutic target for the treatment of OSCC.

MiR-134 targets PDCD7 to reduce E-cadherin expression and enhance oral cancer progression.

Oral squamous cell carcinoma (OSCC) is a common malignancy worldwide. This study clarified the oncogenic role of miR-134 in OSCC. Reporter assays, using both wild-type and mutant constructs, confirmed that Programmed Cell Death 7 (PDCD7) gene was a potential target of miR-134. The OSCC cells exogenously expressed miR-134 exhibited reduced PDCD7 expression. As expected, exogenous miRZip-134 expression increased PDCD7 expression in the OSCC cells; additionally, PDCD7 expression suppressed the oncogenicity of the OSCC cells. By contrast, PDCD7 knockout through gene editing increased in vitro oncogenicity and neck nodal metastasis in mice, and reduced E-cadherin (E-cad) expression. PDCD7 transactivated E-cad expression via the GC-box in the promoter. Moreover, miR-134-associated cellular transformation and E-cad downregulation was attenuated by PDCD7. Downregulation of both PDCD7 and E-cad and high levels miR-134 expression was observed in OSCC tumor tissues. Activation of the miR-134-PDCD7-E-cad pathogenesis cascade occurred early during the human and murine oral carcinogenesis process. In conclusion, the oncogenic effect of miR-134 in oral carcinoma is mediated by reducing PDCD7 and E-cad expression.

Overexpression of miR-155 promotes the proliferation and invasion of oral squamous carcinoma cells by regulating BCL6/cyclin D2.

Although microRNA-155 (miR-155) is known to play an important role in many cancers, its expression and function in oral squamous cell carcinoma (OSCC) was not fully understood. Thus, in the present study, we investigated the expression of miR-155 and also the role this miR plays in OSCC. We used the OSCC cell line (CAL27) and paired tumor and non-tumor tissue samples from patients with OSCC in order to detect the expression of miR-155. Cell proliferation, migration and invasion assays were then undertaken in order to determine the effect of miR-155 on the biological behavior of CAL27 cells following transient transfection with miR-155 mimic and antagomir. The regulatory effect of miR-155 on its target gene B-cell CLL/lymphoma 6 (BCL6) and downstream gene cyclin D2 (CCND2) was also analyzed. We found that miR-155 expression in OSCC cell and tumor tissues was significantly higher than that of the controls. We noted that the miR-155 mimic enhanced CAL27 cell proliferation, migration and invasion ability, downregulated BCL6 levels, and increased cyclin D2 expression. However, we noted that abrogating miR-155 with the miR-155 antagomir suppressed CAL27 cell proliferation, migration and invasion, upregulated BCL6 and reduced cyclin D2 expression. These results indicate that miR-155 plays a tumor-promoting role in OSCC by regulating the BCL6/cyclin D2 axis.

Overexpression of proteasomal activator PA28α serves as a prognostic factor in oral squamous cell carcinoma.

BackgroundDespite recent advances in oral squamous cell carcinoma (OSCC) diagnosis and therapy, disease recurrence remains common and is strongly associated with mortality. It is therefore critical to identify new targets for both treatment and diagnostic purposes. We aimed at investigating the role of PA28α, a proteasomal activator in OSCC.MethodsThe expression of PA28α was examined in a panel of OSCC cell lines and tissues, associated with oncomine analysis. In a large OSCC patient cohort, the prognostic value of PA28α expression was evaluated. Primary clinical end points were recurrence-free and overall survival rate. Functional involvement of PA28α in OSCC was examined in both in vitro and in vivo models upon specific siRNA knockdown.ResultsPA28α was found to be overexpressed in OSCC cell lines and tumor tissues. High expression of PA28α was significantly associated with recurrence and poorer overall survival. Specific knockdown of PA28α inhibited OSCC cell proliferation, migration, invasion in vitro and reduced the growth of OSCC xenografts in vivo. Multivariate Cox regression analyses revealed PA28α as independent prognostic predictors.ConclusionsThese results suggest that PA28α is involved in OSCC oncogenesis and may serve as a potential prognostic factor.Electronic supplementary materialThe online version of this article (doi:10.1186/s13046-016-0309-z) contains supplementary material, which is available to authorized users.

MiR-138 suppresses the proliferation of oral squamous cell carcinoma cells by targeting Yes-associated protein 1.

Aberrant microRNA expression has been suggested to be an important event in the pathologies of various types of cancer. MicroRNA-138 (miR-138) has been reported to be frequently downregulated in various types of human cancer, including oral squamous cell carcinoma (OSCC). However, the precise molecular mechanism of miR-138 underlying OSCC remains largely unknown. The aim of the present study was to investigate the expression of miR-138 in OSCC tumor tissues and several OSCC cell lines and validated its interaction with the 3'-untranslated region (3'-UTR) of Yes-associated protein 1 (YAP1). The results showed that, miR-138 was significantly downregulated in OSCC tumor tissues and cell lines. Overexpression of miR-138 inhibited cell proliferation of OSCC cells whereas the downregulation of miR-138 promoted cell proliferation. A direct interaction between miR-138 and 3'-UTR of YAP1 was validated by dual-luciferase reporter assay. Moreover, overexpression of miR-138 in OSCC cells significantly decreased the expression of YAP1 and downregulation of miR-138 inhibited the expression of YAP1. Specifically, the inhibitory effect of miR-138 on the proliferation of OSCC cells was eliminated by transfection with YAP1 overexpression vectors that did not harbor any specific miR-138 binding specific sequences in 3'-UTR. In addition, the miR-138‑overexpressing OSCC cells exhibited a low growth rate in the xenograft tumor assay with a decreased expression of YAP1 in tumor tissues. The results suggest that miR-138 is a tumor suppressor miRNA in OSCC through targeting YAP1, which serves as a promising therapeutic target for the treatment of OSCC.

Associations between proteasomal activator PA28γ and outcome of oral squamous cell carcinoma: Evidence from cohort studies and functional analyses

SummaryBackgroundPA28γ was suggested to play a role in malignant progression. This paper aimed to investigate the association between PA28γ and the prognosis of oral squamous cell carcinoma (OSCC) in cohort studies.MethodsThe PA28γ expression level was assessed by immunohistochemistry in a total of 368 OSCC patients from three independent cohorts. The Cox proportional hazards regression model was used to determine multivariate hazard ratios for Overall Survival (OS). Model discrimination was measured using C Statistic. Additionally, OS was analyzed in Head Neck Squamous Cell Carcinoma (HNSCC) patients from The Cancer Genome Atlas (TCGA) data set. Functional analyses were conducted both in-vitro and in-vivo.FindingsThe median follow-up times of patients in the three studies were 60, 52, and 51 months. High expression of PA28γ was identified in tumors from 179 of 368 patients (48.6%). Compared with low expression, high expression of PA28γ was strongly associated with worse OS, with relative risks of 5.14 (95% CI, 2.51–10.5; P < 0.001), 2.82 (95% CI, 1.73–4.61; P < 0.001), and 3.85 (95% CI, 1.59–9.37; P = 0.003). PA28γ expression was also associated with disease-free survival in all three cohorts (P < 0.005). These findings are consistent with TCGA HNSCC data (P < 0.006). The prediction of all-cause mortality was significantly improved when PA28γ was added to the traditional clinical factors (Model 3, C statistic value: 0.78 VS 0.73, P = 0.016). In functional analyses, we found that PA28γ silencing dramatically inhibited the growth, proliferation and mobility of OSCC cells in vitro and reduced tumor growth and angiogenesis in tumor-bearing mice.InterpretationPA28γ overexpression is associated with adverse prognosis in patients with OSCC. The aberrant expression of PA28γ may contribute to the pathogenesis and progression of OSCC.Research in contextOSCC is one of the most common HNSCC, which have a high lethally rate. However, few prognostic markers have been applied in the clinical practice. We found that PA28γ in OSCC tumor tissues were significantly high expression than those in normal tissues. As the results of the three cohorts from two independent research centers and from an additional validation cohort from a US population in the TCGA dataset, we demonstrate PA28γ is a good predictor of the risk of death in OSCC. Meanwhile, we demonstrate PA28γ have a potential role in OSCC tumorigenesis.

Micro-ribonucleic acid 143 (MiR-143) inhibits oral squamous cell carcinoma (OSCC) cell migration and invasion by downregulation of phospho-c-Met through targeting CD44 v3

The aim of this study was to investigate the roles and mechanisms of Micro-ribonucleic acid 143 (miR-143) in oral squamous cell carcinoma cells. Following the detection of miR-143 expression, cell proliferation, migration, and invasion assays and Western blot analysis were conducted in the oral squamous cell carcinoma (OSCC) cell lines. We found that the expression of miR-143 was significantly decreased in the OSCC cell lines (SCC-4, Tca-8113, CAL-27) and tumor tissues. Meanwhile, miR-143 was significantly correlated with the migration and invasion in OSCC cell lines. Further investigation revealed that the expression level of miR-143 was opposite to that of its potential target gene-CD44 v3 and was also related to phospho-c-Met activation. miR-143 could exert significantly suppressive effects on the ability of migration and invasion in OSCC cell lines, and the mechanism of this might be related to the activity of phospho-c-met though the CD44 v3/HGF signal. miR-143 could thus provide new applications for the treatment of OSCC.

Phosphorylated Signal Transducer and Activator of Transcription-1 Immunohistochemical Expression Is Associated With Improved Survival in Patients With Oral Squamous Cell Carcinoma

To estimate whether the immunohistochemical (IHC) expression patterns of the tumor suppressor gene signal transducer and activator of transcription-1 (STAT1) and its active phosphorylated form (PSTAT1) serve as potential prognostic and predictive markers in patients with oral squamous cell carcinoma (OSCC). STAT1 and PSTAT1 protein expressions were examined immunohistochemically in OSCC tumor tissues and adjacent normal mucosa from 49 patients who underwent primary surgery. The IHC scores were correlated with all available clinicopathologic parameters that were obtained from a maximum of 7 years of follow-up, including survival and response to adjuvant therapy treatment. There was a shift toward lower percentages of cells with STAT1 (P < .014) and PSTAT1 (P < .001) detected in OSCC tumors compared with adjacent normal tissue sites. No association with patients' clinicopathologic characteristics was shown. However, for the group of patients who received adjuvant chemotherapy, increased PSTAT1 intensity of staining in OSCC tumors was strongly associated with better overall survival (P = .008). This is the first study to concurrently evaluate STAT1 and PSTAT1 IHC expression patterns and their prognostic significance in patients with OSCC, highlighting the potential role of PSTAT1 as a biomarker in therapeutic decision making. Large prospective studies are needed to verify these findings.

Abstract C29: Association of interferon-induced protein with tetratricopeptide repeats 1 gene family with human papilloma virus infection in patients with oral squamous cell carcinoma

Abstract Interferon-induced protein with tetratricopeptide repeats 1 (IFIT1) gene family is one of most responsive interferon-stimulated gene families. Four members have been characterized in humans, namely, IFIT1, IFIT2, IFIT3, and IFIT5. The encoded proteins mediate a variety of protein—protein interactions by tetratricopeptide repeat helix-turn-helix motifs to modulate on cellular functions, such as translation initiation, double-stranded RNA-induced signaling, cell proliferation and migration. We have previously demonstrated that IFIT2 silencing activates atypical PKC signaling and induces epithelial-mescenchymal transition (EMT), cell migration, invasion, and metastasis of oral squamous cell carcinoma (OSCC) cells in cultured or animal models. Our results also showed that IFIT2 is potentially a prognosis biomarker of patients with OSCC. In the present study, we further explore the roles of IFIT1 family proteins involved in the regulatory mechanism of metastasis in OSCC cells. We first confirmed that the proteins of various IFIT1 family members are significantly induced by interferon in a dose-dependent manner. We further characterized the expression of IFIT1, IFIT3, and IFIT5 proteins in patients with OSCC. Our present results revealed that most OSCC tumor tissues expressed a variety of amounts of IFIT2 proteins by immunohistochemical analysis. Although the expression levels of IFIT1 and IFIT3 were relatively lower than IFIT2, we observed a close association between IFIT1 and IFIT3 protein expression in OSCC patient-derived tumor specimens. Numerous studies have pointed out that human papillomavirus (HPV) infection is associated with a high risk of oral cancer. Among these 4 IFIT1 family members, we preliminarily demonstrated a well correlation between HPV E6 and IFIT5 protein expression in tumor specimens of OSCC patients, implying a critical role of IFIT5 in response of HPV infection. Accordingly, our present studies implicate that all IFIT1 family are activated by interferon but each member apparently participates in different cellular activities. Their roles involving in OSCC metastasis warrant our further investigation. Citation Format: Ai-Hsin Yen, Kuo-chu Lai, Ying-Chen Chen, Chung-Ji Liu, Kuo-Wei Chang, Te-Chang Lee. Association of interferon-induced protein with tetratricopeptide repeats 1 gene family with human papilloma virus infection in patients with oral squamous cell carcinoma. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Invasion and Metastasis; Jan 20-23, 2013; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2013;73(3 Suppl):Abstract nr C29.

Abstract A81: Lyophilized black raspberries modulate survivin/BIRC5 in oral squamous cell carcinomas

Abstract Purpose: Cancer chemoprevention is the use of natural or synthetic agents, in combination or alone, to inhibit, delay or reverse the carcinogenic process, and is an active topic of cancer research. Numerous epidemiological studies have shown the strong correlation between the consumption of fresh fruits and vegetables and a decreased cancer risk. With a food-based approach to cancer prevention, emphasis is placed on the potential for complex mixtures of preventive agents in whole food to inhibit multiple process of carcinogenesis. In support of this approach, our laboratory conducted several preclinical animal studies that demonstrate the remarkable chemopreventive activities of black raspberries on chemically-induced oral squamous cell carcinoma (OSCC). We have shown that an extract of lyophilized black raspberries (LBR) dramatically inhibits the in vitro proliferation of cells derived from human OSCC, suggesting that the chemoprevention of oral cancer by LBR components in vivo is possible. Survivin (BIRC5) is a member of the Inhibitor of Apoptosis (IAP) family of caspase inhibitors that direct the negative regulation of apoptosis. BIRC5 is highly expressed in most human tumors, including oral squamous cell carcinoma (OSCC), but nearly undetectable in terminally differentiated normal adult tissues. BIRC5 acts to antagonize apoptosis in tumors and to promote resistance to common apoptotic-inducing therapies such as ionizing radiation. A series of studies examining BIRC5 in OSCC have associated increased BIRC5 expression levels with cancer progression and poor prognosis. The current study reports the LBR-dependent modulation of BIRC5 expression in OSCCs as part of an ongoing Phase I clinical trial. Methods: According to protocols approved by the Internal Review Board (IRB) of The Ohio State University, 24 biopsy-confirmed OSCC patients were administered three LBR troches 4x/day (4.3g cumulative dose) between presurgical enrollment and their normally scheduled surgery. Biopsies were obtained from distant high “at-risk normal” (N1) and tumor (T1) tissues at enrollment and following LBR exposure (N2, T2) acquired during surgical resection [exposure 2.5–34 days (mean exposure = 11.2±7.2 days)]. Pre-validated TaqMan gene expression assays were used to assess apoptosis-related genes for LBR-dependent expression changes. Results: OSCC tumor samples had significantly greater BIRC5 expression compared to the high “at-risk normal” oral samples, both prior to (T1 vs N1, p&amp;lt;0.0001) and following (T2 vs N2, p=0.0115) LBR administration. In the high “at-risk normal” oral samples, there was no significant difference in BIRC5 expression between the pre- and post-LBR treatment groups (N2 vs N1, p=0.1425). There was a statistically significant decrease in tumor BIRC5 expression after LBR exposure (T2 vs T1, p=0.0199). Conclusions: BIRC5 expression was significantly decreased in OSCC tumor tissues following short-term exposure to LBR as part of an ongoing Phase 1 clinical trial. Consequently, down-regulation of BIRC5 expression following administration of LBR to OSCC patients may provide mechanistic insight for future food-based cancer risk reduction interventions. Citation Information: Cancer Prev Res 2010;3(1 Suppl):A81.