Co-inhibition of adenosine 2b receptor and programmed death-ligand 1 promotes the recruitment and cytotoxicity of natural killer cells in oral squamous cell carcinoma.

Adenosine promotes anti-tumor immune responses by modulating the functions of T-cells and natural killer (NK) cells in the tumor microenvironment; however, the role of adenosine receptors in the progression of oral squamous cell carcinoma (OSCC) and its effects on immune checkpoint therapy remain unclear. In this study, we obtained the tumor tissues from 80 OSCC patients admitted at the Shandong University Qilu Hospital between February 2014 and December 2016. Thereafter, we detected the expression of adenosine 2b receptor (A2BR) and programmed death-ligand 1 (PD-L1) using immunohistochemical staining and analyzed the association between their expression in different regions of the tumor tissues, such as tumor nest, border, and paracancer stroma. To determine the role of A2BR in PD-L1 expression, CAL-27 (an OSCC cell line) was treated with BAY60-6583 (an A2BR agonist), and PD-L1 expression was determined using western blot and flow cytometry. Furthermore, CAL-27 was treated with a nuclear transcription factor-kappa B (NF-κ B) inhibitor, PDTC, to determine whether A2BR regulates PD-L1 expression via the NF-κ B signaling pathway. Additionally, a transwell assay was performed to verify the effect of A2BR and PD-L1 on NK cell recruitment. The results of our study demonstrated that A2BR and PD-L1 are co-expressed in OSCC. Moreover, treatment with BAY60-6583 induced PD-L1 expression in the CAL-27 cells, which was partially reduced in cells pretreated with PDTC, suggesting that A2BR agonists induce PD-L1 expression via the induction of the NF-κ B signaling pathway. Furthermore, high A2BR expression in OSCC was associated with lower infiltration of NK cells. Additionally, our results demonstrated that treatment with MRS-1706 (an A2BR inverse agonist) and/or CD274 (a PD-L1-neutralizing antibody) promoted NK cell recruitment and cytotoxicity against OSCC cells. Altogether, our findings highlight the synergistic effect of co-inhibition of A2BR and PD-L1 in the treatment of OSCC via the modulation of NK cell recruitment and cytotoxicity.

Dysbiotic tumor microbiota associates with head and neck squamous cell carcinoma outcomes.

BACKGROUND: The need for an effective tool to predict prognosis of head and neck squamous cell carcinoma (HNSCC) patients is critical and unmet. Microbiota has recently been found involved in tumor progression and response to immunotherapy. However, the association of microbiota with the prognosis of HNSCC patients remains obscure. This study aims to investigate the association between tumor microbiota and outcomes of HNSCC patients. METHODS: A retrospective study including 129 primary tumors of HNSCC was conducted. Using 16S rRNA sequencing, the profile and the composition of tumor microbiota were measured and their associations with overall survival (OS) and disease free survival (DFS) were examined. RESULTS: We observed a reduced richness and enriched abundances of genera Schlegelella and Methyloversatilis in tumor microbiota of HNSCC patients with poor prognosis. However, a richer tumor microbiota with greater abundances of genera Bacillus, and Lactobacillus and Sphingomonas was characterized in the patients with favorable prognosis.The ratio of these differentially abundant taxa, microbial dysbiosis index (MDI), was significantly associated with OS (hazard ratio [HR], 4.67, 95% confidence interval [CI], 2.51 to 8.69,P < 0.001) and DFS (HR, 2.89; 95% CI, 1.74 to 4.80, P < 0.001) independently of age, tumor size, lymph node metastasis, differentiation and p16 status. The risk score of multivariate Cox regression exhibited an excellent performance for estimating three-year OS (AUC of 0.826). We also found a richer tumor microbiota was correlated with moderate peritumoral inflammatory infiltration. CONCLUSION: These results indicate that tumor microbiota associates with outcomes of HNSCC patients.

C1QTNF6 promotes oral squamous cell carcinoma by enhancing proliferation and inhibiting apoptosis.

BACKGROUND: C1QTNF6 (CTRP6), a member of the CTRP family, has recently been implied to play a role in the tumorigenesis of for a variety of cancer types. However, the role of C1QTNF6 in oral squamous cell carcinoma (OSCC) and its potential molecular remains unclear. METHODS: C1QTNF6 expression was detected by qRT-PCR and western blot analysis. Lentiviral vectors were constructed to knockdown C1QTNF6 in CaL27 and SCC-9 human OSCC cell lines. Cell viability, cell cycle and cell apoptosis analyses were performed by MTT assay, PI/Annexin V staining, and flow cytometry. The effect of C1QTNF6 knockdown on in vivo tumorigenicity of OSCC cells in vivo was evaluated using nude mouse xenograft tumor model. Downstream signaling mechanisms were identified by microarray and Ingenuity Pathway Analysis. RESULTS: Immunohistochemistry of OSCC tissue and data from TCGA demonstrate that C1QTNF6 was overexpressed in OSCC tissues, and that cellular proliferation was significantly decreased after C1QTNF6 was knockdown in CaL27 and SCC-9 cell lines. Knockdown of C1QTNF6 also resulted in cell cycle arrest at the G2/M phase and enhanced cell apoptosis in in CaL27 and SCC-9 cell lines. Furthermore, knockdown of C1QTNF6 in Cal-27 cells inhibited tumor growth of OSCC in vivo. Microarray analysis revealed that C1QTNF6 silencing resulted in significant alterations of gene expression, with the Acute Phase Response signaling pathway significantly activated following C1QTNF6 silencing. CONCLUSIONS: These results suggest that C1QTNF6 plays an important role in promoting OSCC tumorigenesis, which indicates that C1QTNF6 may comprise a promising therapeutic target for OSCC treatment.

Preoperative neutrophil lymphocyte ratio but not platelet lymphocyte ratio predicts survival and early relapse in patients with oral, pharyngeal, and lip cancer.

BACKGROUND: To evaluate the prognostic value of preoperative neutrophil lymphocyte ratio (NLR) and platelet lymphocyte ratio (PLR) in oral, pharyngeal, and lip cancer for survival and relapse. METHODS: Clinic-pathologic and hematological records were retrospectively retrieved. Patients completed follow-up period were included for survival and relapse analysis. RESULTS: The preoperative NLR value was a prognostic factor for both overall survival and relapse-free survival. The high NLR group demonstrated higher total relapse rate, higher local relapse rate, and higher relapse rate within 12 months. However, the preoperative PLR did not associate with survival or relapse. CONCLUSIONS: The preoperative NLR, not PLR, is an independent prognostic indicator of survival. It also exhibits predictive value for relapse, particularly early relapse within 12 months. The preoperative NLR value might be recommended as a useful tool for predicting the outcomes and stratifying patients for different management strategies.

Carcinoembryonic antigen cell adhesion molecule 1 inhibits the antitumor effect of neutrophils in tongue squamous cell carcinoma.

Carcinoembryonic antigen cell adhesion molecule 1 (CEACAM1), a transmembrane glycoprotein, has multiple functions. In tongue squamous cell carcinoma (TSCC), CEACAM1 overexpression is correlated with neutrophil infiltration, and both are associated with poor clinical outcomes. However, the mechanism underlying CEACAM1's effect on neutrophil function in TSCC remains unclear. We cocultured tongue carcinoma cells overexpressing CEACAM1-4L, CEACAM1-4S and differentiated HL-60 cells. This significantly upregulated the expression of MMP-9, interleukin 8, and VEGF-A in the differentiated HL-60 cells and downregulated the expression of TNF-α, relative to vector and blank control groups (P < 0.05). Additionally, CEACAM1 overexpression in tongue carcinoma cells weakened the cytotoxicity of differentiated HL-60 cells in the coculture system (P < 0.05). Thus, CEACAM1 expression in TSCC may induce an antitumor to protumor transformation of neutrophils. We performed qRT-PCR and ELISA to evaluate the underlying mechanism, and found that CEACAM1 expression in tongue carcinoma cells upregulated transforming growth factor ß1 (TGF-ß1) expression, while blocking of TGF-ß1 inhibited the neutrophils' changes in the coculture system. Immunohistochemical analysis of clinical specimens revealed strong expression of TGF-ß1 protein in TSCC. TGF-ß1 expression was positively correlated with CEACAM1 expression, lymph node metastasis, and tumor recurrence. Double immunofluorescence results revealed colocalization of CEACAM1 and TGF-ß1 protein in TSCC. A xenograft nude mouse model revealed that CEACAM1 overexpression in TSCC promoted tumor formation and growth, and was associated with more neutrophils infiltration. Our results indicate that CEACAM1 overexpression in TSCC may induce transformation of neutrophils from antitumor to protumor type via TGF-ß1, which may further promote tumor progression.

Endothelial cells modified by adenovirus vector containing nine copies hypoxia response elements and human vascular endothelial growth factor as the novel seed cells for bone tissue engineering.

Vascularization is one of the hotspots during the development of new therapeutic strategies for bone tissue engineering, which can alleviate hypoxic circumstance and prevent transplant failure. Vascular endothelial growth factor (VEGF) gene transfection using recombinant adenovirus (Ad) vector can effectively promote angiogenesis, but uncontrolled long-term continuous expression of VEGF brings safety concern. Here we constructed a recombinant Ad vector containing nine copies of HRE promoter and the hVEGF165 gene, which conserved the oxygen sensitivity of hypoxia-inducible factor-1/hypoxia response elements (HIF-1/HRE). After transfection into human umbilical vein endothelial cells (HUVEC), the hVEGF165 mRNA and protein levels were much higher in response to hypoxia, as revealed by RT-PCR and ELISA, respectively. Furthermore, Ad-9HRE-hVEGF165 vector effectively promoted proliferation, migration and tube formation of HUVEC under hypoxic conditions. Thus we believe that the Ad-9HRE-hVEGF165 vector can contribute to the regulation of vascularization, which may provide a new approach for a better control of the expression of hVEGF165 during bone tissue engineering.

Kif4A mediate the accumulation and reeducation of THP-1 derived macrophages via regulation of CCL2-CCR2 expression in crosstalking with OSCC.

Crosstalk between tumor infiltrating macrophages and tumor cells is thought to play an indispensable role in oral squamous cell carcinomas (OSCC) by induction and maintenance of tolerance microenvironment. High infiltration of M2 macrophages and increasing expression of Kinesin family member 4A (Kif4A) in primary OSCC have been proved to correlate with greater tumoral size and poor clinical outcome. However, linkage between Kif4A and infiltrating macrophages in tumorigenesis and progression remains unclear. In the present study, we show that, the interaction between THP-1derived macrophage and OSCC cell line Cal-27 may up-regulate the Kif4A expression in both of them. Additionally, elevated soluble CCL2 in medium and more expression of CCR2 on macrophage were observed during the crosstalk. SiRNA of Kif4A and neutralizing antibody of CCL2 were utilized to identify that; increasing Kif4A can promote the recruitment of macrophages towards Cal-27 and educate them to M2 polarized macrophages via regulating CCL2/CCR2. In combination, the results of the present study may provide interesting clues to understanding the Kif4A-CCL2/CCR2-macrophage axis as a novel therapeutic target to improve the clinical outcome of OSCC.

Kif4 regulates the expression of VEGFR1 through the PI3K/Akt signaling pathway in RAW264.7 monocytes/macrophages.

Kinesin superfamily protein 4 (Kif4), a microtubule-based motor protein, has been shown to participate in a number of critical cellular processes, such as cell division, the intracellular transport of membranous vesicles and signal transduction. However, whether KIF4 regulates vascular endothelial growth factor (VEGF) receptor 1 (VEGFR1) expression remains unknown. Thus, in this study, in order to examine the effects of Kif4 on the expression of VEGFR1 in RAW264.7 monocytes/macrophages, Kif4 was silenced using siRNA. RT-qPCR, western blot analysis and ELISA were used to assess the expression of Kif4 and VEGFR1 up- and downstream signaling molecules, including VEGF-A, VEGFR1, soluble form of VEGFR1 (sVEGFR1), phosphorylated (p-)Akt and Akt. The silencing Kif4 inhibited the mRNA expression of VEGF (P<0.01) and p-Akt (P<0.05); however, the level of VEGF-A was increased (P<0.05) compared with the negative control siRNA-transfected group. The silencing of Kif4 decreased the VEGFR1 mRNA (P<0.05), VEGFR1 protein and sVEGFR1 levels in the cell supernatant (P<0.01). Following the application of insulin-like growth factor-1 (100 ng/ml), the specific agonist of PI3K/Akt in the Kif4 siRNA-transfected group, the VEGFR1 mRNA levels (P<0.001), the VEGFR1 protein levels and the sVEGFR1 (P<0.01) levels significantly increased; however, the levels of VEGF in the cell supernatant were decreased (P<0.05). Taken together, these findings suggest that Kif4 regulates the expression of VEGFR1 in RAW264.7 cells and that the PI3K/Akt pathway is involved in this process.

Fucoidan reduced the invasion of oral squamous cell carcinoma cells and modified their effects to macrophages.

Fucoidan is a complex of polysaccharides showing antitumor and immunomodulation properties. Our previous studies found its regulation to myeloid immune cells, including macrophages. Aberrant infiltration and functions of macrophages are commonly found in oral squamous cell carcinoma (OSCC). In this study, we analyzed the effects of fucoidan on invasion of OSCC cells, and their regulation to macrophages, trying to evaluate its role as a potential therapy for OSCC. CAL27 and THP-1-derived macrophages were used as models for OSCC cells and tumor-infiltrated macrophages in the in vitro study, respectively. The effects of fucoidan on invasion of OSCC cells and their recruitment to macrophages were analyzed by transwell assay. KIF4A siRNA transfection was performed to investigate its role in fucoidan-modulated OSCC cells invasion. CCL3-neutralizing antibody was added into the conditioned medium of OSCC cells to evaluate its role in fucoidan-mediated macrophages recruitment and re-education. Fucoidan reduced the invasive potential of CAL27 cells with a decrease of MMP-2 and KIF4A transcription. KIF4A knockdown in CAL27 cells led to decreased invasion and MMP-2 expression. The conditioned medium of fucoidan-treated CAL27 cells promoted recruitment and inflammatory cytokines secretion on THP-1-derived macrophages. Further analysis found that fucoidan increased CCL3 production in CAL27 cells. Blocking CCL3 expression reversed the effects of fucoidan on macrophage recruitment and re-education. Our study found that fucoidan regulated the invasion of OSCC cells and also their recruiting and re-educating effects on macrophages, suggesting it could be a complementary approach in the treatment of OSCC.

Interleukin-4 and granulocyte-macrophage colony-stimulating factor mediates the upregulation of soluble vascular endothelial growth factor receptor-1 in RAW264.7 cells-a process in which p38 mitogen-activated protein kinase signaling has an important role.

BACKGROUND/PURPOSE: Soluble vascular endothelial growth factor receptor-1 (sVEGFR1) antagonizes angiogenesis by inhibiting the biological function of vascular endothelial growth factor (VEGF). Immature dendritic cells (imDCs) express high levels of sVEGFR1 during development and are antiangiogenic. This study aimed to investigate the changes in VEGFR1, sVEGFR1, and VEGF levels during the development of imDCs and explore the underlying signaling mechanisms. METHODS: To model the differentiation of imDCs from monocytes, RAW264.7 cells, a murine monocyte/macrophage cell line, were stimulated by interleukin-4 (IL-4; 10 ng/mL, 20 ng/mL, and 40 ng/mL) and/or by granulocyte-macrophage colony-stimulating factor (GM-CSF; 10 ng/mL, 20 ng/mL, and 50 ng/mL) and/or pretreated by the p38 inhibitor SB203580. The levels of VEGFR1, sVEGFR1, and VEGF were detected by reverse transcription polymerase chain reaction (RT-PCR), Western blot, and enzyme-linked immunosorbent assay (ELISA). RESULTS: IL-4 increased the VEGFR1 mRNA and sVEGFR1 levels in RAW264.7 (p < 0.05). This increase was inhibited by SB203580. Granulocyte-macrophage colony-stimulating factor increased the sVEGFR1 levels, but it had no significant effect on VEGFR1 mRNA levels. SB203580 decreased the expression of VEGFR1 mRNA induced by GM-CSF, whereas sVEGFR1 was unaffected. IL-4 had a greater effect on sVEGFR1 levels, compared to GM-CSF. CONCLUSION: IL-4 and GM-CSF increased sVEGFR1 levels, but did not significantly effect VEGF expression, and led to the antiangiogenesis properties of monocytes. p38 Mitogen-activated protein kinase signaling has an important role in the process.

Effects of human Dachshund homolog 1 on the proliferation, migration, and adhesion of squamous cell carcinoma of the tongue.

OBJECTIVE: To investigate the expression and role of human Dachshund homolog 1 (DACH1) in the tongue squamous cell carcinoma (TSCC). STUDY DESIGN: To explore the expression, regulation, and mechanism of DACH1 in TSCC, nine samples of fresh tumor and adjacent tissues, 51 samples of paraffin-embedded TSCC and paired adjacent tissues, and TSCC cell line SCC-25 were examined. Immunohistochemistry, real-time polymerase chain reaction, Western blot, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, colony formation, Transwell, adhesion assays, and flow cytometry were used. RESULTS: The DACH1 expression level was significantly lower in tumors than in the adjacent tissues, and such low expression was associated with poor differentiation of tumors, late clinical stage, and lymph node metastasis. Moreover, overexpression of DACH1 might promote apoptosis and inhibit the proliferation, migration, and adhesion of SCC-25 cells. CONCLUSIONS: DACH1 may be a potential molecular target for the therapy of recurrent and metastatic TSCC.

Ischemia preconditioning protects rat submandibular glands from ischemia/reperfusion injuries.

To investigate the effects of ischemia/reperfusion on rat submandibular glands without denervation and the possible protective effects of ischemia preconditioning on the glands that experienced ischemia/reperfusion, in-situ ischemia/reperfusion and ischemia preconditioning experimental models of submandibular glands of healthy male Wistar rats were conducted. For ischemia/reperfusion groups, the glands were subjected to 90 min of ischemia without denervation, followed by 1, 12, 24, or 72 h of reperfusion. Ischemia preconditioning was achieved by 3 min of ischemia following 3 min of reperfusion, performed three times before ischemia/reperfusion. Salivary secretion, histological changes, alterations of tight junctions, myeloperoxidase activity, cellular apoptosis, and reactive oxygen species levels were detected. In ischemia/reperfusion glands, rising acute-inflammation responses, reduced tight-junction width, and increased myeloperoxidase activity, reactive oxygen species levels, and apoptotic cell numbers were observed, along with secretory dysfunction, especially at 1 and 12 h post-reperfusion, which seemed to gradually return to normal by 72 h post-reperfusion. In contrast, ischemia preconditioning showed the potential to ameliorate the injury-stress responses caused by ischemia/reperfusion. Our study revealed that ischemia/reperfusion could cause a series of injury-stress responses and ultimately lead to hyposecretion, independently of the parasympathetic nerve supply, which might play an important role in the early-phase dysfunction of the transplanted glands. Ischemia preconditioning could protect the involved glands and improve ischemia/reperfusion-induced hyposecretion.

[Effect on secretory function of rat submandibular glands caused by ischemia reperfusion].

OBJECTIVE: To investigate the injury stress responses caused by ischemia reperfusion and its effects on the salivary secretory function of rat submandibular glands. METHODS: An in situ ischemia reperfusion experimental model of rat submandibular glands was developed. The rat submandibular glands were subjected to 90 min of ischemia without denervation followed by reperfusion for 1, 12, 24, and 72 h. Salivary secretion, histological changes, reactive oxygen species (ROS) levels, and cellular apoptosis of the involved submandibular glands were detected after reperfusion. RESULTS: The secretory function of the glands decreased at 1 and 12 h, and the saliva secretion gradually had the same value as that of the control sample 72 h after reperfusion. Increasing inflammatory cells infiltration, cellular atrophy, and tissue edema were observed especially after reperfusion for 12 h. The level of ROS and the number of apoptotic cells exhibited the same tendency, and higher ROS levels and more apoptosis cells 1 and 12 h after reperfusion were observed. CONCLUSION: Our study suggests that ischemia reperfusion can cause a series of injury stress responses in submandibular glands, which might have an important function in the early phase dysfunction of transplanted submandibular glands.

In situ expression and serum level of thymic stromal lymphopoietin in oral lichen planus.

BACKGROUND: Oral lichen planus (OLP) is a chronic inflammatory disease of oral mucosa in which the CD8(+) T cell-mediated cytotoxicity is regarded as a major mechanism of pathogenesis. The main objective of this study is to investigate in situ expression and secretion of thymic stromal lymphopoietin (TSLP) in specimens and sera from patients with oral lichen planus. METHODS: Thirty-six patients with OLP and 35 donors enrolled in specimen and serum collection. Immunohistochemical method and immunofluorescence double-staining method were used to detect the expression of thymic stromal lymphopoietin and its receptor (TSLPR) together with CD8 in OLP specimens. Enzyme-linked immunosorbent assay (ELISA) was used to detect TSLP secretion. RESULTS: More TSLP- or TSLPR-positive cells showed in OLP specimens than in normal controls, and TSLP-positive cells were mainly in the epithelium, while TSLPR-positive cells mainly in the lamina propria. Furthermore, the number of TSLP-positive cells in the stratum basal was associated with the amount of mononuclear cells infiltrating in the lamina propria of OLP specimens. Among infiltrating mononuclear cells in the lamina propria, some CD8-positive cells also expressed TSLPR. The TSLP serum level of patients with OLP was significantly higher than of healthy donors, but there was no statistically difference between two clinical subtypes of OLP. CONCLUSIONS: Our findings provided the first evidence that TSLP may enroll in the pathology of OLP and the TSLP-TSLPR interaction may play an important role in it.

Neutrophils infiltration in the tongue squamous cell carcinoma and its correlation with CEACAM1 expression on tumor cells.

OBJECTIVE: The present study aimed to explore the clinical significance of neutrophils infiltration and carcinoembryonic antigen related cell adhesion molecule 1 (CEACAM1) expression in the tongue squamous cell carcinoma (TSCC), and to probe the possible relationship between them. MATERIALS AND METHODS: Tissue microarray and immunohistochemistry were used to detect neutrophils density and CEACAM1 expression in 74 cases of primary TSCC specimens and 17 cases of corresponding peritumoral tissues. The relationship of CEACAM1 expression and neutrophils density with clinicopathologic parameters and cancer-related survival of TSCC patients were evaluated. The correlation between CEACAM1 expression and neutrophils density was also evaluated. Real-time quantitative transcription polymerase chain reaction (qRT-PCR) was used to explore the possible molecular mechanisms between CEACAM1 expression and neutrophils infiltration. RESULTS: Immunohistochemistry evaluation revealed that there was more neutrophils infiltration in TSCC tissues than in peritumoral tissues. High neutrophil density was associated with LN metastasis (P=0.01), higher clinical stage (P=0.037) and tumor recurrence (P=0.024). CEACAM1 overexpression was also associated with lymph node metastasis (P=0.000) and higher clinical stage (P=0.001). Survival analysis revealed that both neutrophils infiltration and CEACAM1 overexpression were associated with poorer cancer-related survival of TSCC patients (P<0.05), and neutrophils infiltration was an independent prognostic factor for TSCC (P<0.05). Furthermore, overexpression of CEACAM1 was correlated with more neutrophils infiltration in TSCC tissues (P<0.01). qRT-PCR results showed that CEACAM1-4L can upregulate the mRNA expression of IL-8 and CXCL-6, which were strong chemotactic factors of neutrophils. CONCLUSION: Our results demonstrated that more neutrophils infiltration and overexpression of CEACAM1 were associated with poor clinical outcomes in TSCC tissues. Overexpression of CEACAM1 on tumor cells correlated with more neutrophils infiltration to some extent through upregulating mRNA expression of IL-8 and CXCL-6.

Silencing Kif2a induces apoptosis in squamous cell carcinoma of the oral tongue through inhibition of the PI3K/Akt signaling pathway.

Previous studies have demonstrated that the overexpression of Kif2a is involved in the progression, invasion and metastasis of squamous cell carcinoma of the oral tongue (SCCOT). Few studies have reported the correlation between Kif2a and apoptosis of tumor cells and which signaling pathways Kif2a is involved in remains unclear. The phosphatidylinositol­3­kinase (PI3K)/protein kinase B (Akt) pathway is frequently activated in many types of human cancer. The aim of the present study was to investigate the effects of downregulation of Kif2 expression on the P13K/Akt pathway in Tca8113 cells to determine whether silencing of Kif2 inhibits the P13K/Akt pathway, resulting in cell apoptosis. siRNA vector was constructed, western blot analysis was used to determine RNA interference and flow cytometry was used to determine promotion of Tca8113 cell apoptosis. The results revealed that silencing Kif2a induces apoptosis and decreases the mRNA and protein level of PI3K, Akt and B­cell lymphoma 2 (Bcl­2) in Tca8113 cells. The PI3K-specific agonist insulin­like growth factor 1 (IGF­1) eliminated the upregulation of apoptosis of Tca8113­Kif2a cells by phosphorylation of Akt. The results suggest that silencing Kif2a induces tumor cell apoptosis, at least partially, through the PI3K/Akt signaling pathway.

Prognostic significance of p21, p27 and survivin protein expression in patients with oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) accounts for >80% of head and neck malignancies. p21, p27 and survivin proteins are abnormally expressed in OSCC and have been previously reported to correlate with cell proliferation and apoptosis. However, the prognostic significance of p21, p27 and survivin remains controversial. The aim of the present study was to investigate the association of clinical parameters and prognosis with the levels of p21, p27 and survivin expression in patients with OSCC. The levels of the three biomarkers were evaluated by immunohistochemical staining in specimens from 110 patients with OSCC and each section was scored according to the percentage of positive tumor cells and staining intensity. Log-rank test and Cox proportional hazards regression were performed to assess the correlation between biomarkers and clinical events. The association between the immunoexpression of p21, p27 and survivin and clinical pathological variables were analyzed by the χ2 test and a non-parametric analysis. The expression of p21 in patients with OSCC was found to correlate with the expression of p27 and survivin. The results of the current study revealed that the five-year survival rate was significantly lower in patients with high p21 expression. In addition, the expression of p27 also showed a negative correlation with the five-year survival rate of OSCC, but to a lesser extent. By contrast, the expression of survivin was not a prognostic factor for OSCC. A Kaplan-Meier analysis and Cox proportional hazards model showed that lymph node metastasis and p21 expression were independent prognostic factors of OSCC.

Effects of allogenous periosteal-derived cells transfected with adenovirus-mediated BMP-2 on repairing defects of the mandible in rabbits.

PURPOSE: This report describes the effect of periosteal-derived cells transfected with adenovirus-mediated bone morphogenetic protein-2 (BMP-2) on the repair of mandibular defects in rabbits. MATERIALS AND METHODS: Periosteal-derived cells were transfected with a replication-defective adenoviral vector encoding BMP-2, and the expression of BMP-2 was examined in transfected cells using in situ hybridization and enzyme-linked immunosorbent assay. In addition, the proliferation ability and activity of alkaline phosphatase of transfected cells were examined using the 3-[4,5-dimethylthiazol-2-Yl]-2,5-diphenyltetrazolium bromide method and enzymology, respectively. In vitro critical-size defects (about 10 × 6 mm) were made bilaterally in each rabbit mandible, and individual sites were implanted with tissue-engineered bone modified with an adenovirus construct encoding the recombinant human BMP-2 gene (Ad-BMP-2), tissue-engineered bone without modification, single bioactive glass ceramic, or no implants (control). New bone formation was evaluated by histochemical stain. RESULTS: BMP-2 expression in the supernate of infected cells was detected from the first day after Ad-BMP-2 transfection and remained at a high level for at least 2 weeks. Alkaline phosphatase expression in transfected cells was significantly greater than in uninfected cells. The group of Ad-BMP-2-modified periosteal-derived cells formed more new bone than the other group at any time point. CONCLUSION: Gene-modified tissue-engineered bone grafts have greater osteogenic potential than single tissue-engineered bone and single bioactive glass ceramic graft. Ex vivo Ad-BMP-2 transfer to periosteal-derived cells can increase bone formation in critical-size bone defects. Further studies are needed to determine if modified engineered cells can be developed for safe and effective clinical applications.

Stable gene-silence of Kif2a synergistic with 5-fluorouracil suppresses oral tongue squamous cell carcinoma growth in vitro and in vivo.

OBJECTIVE: Squamous cell carcinoma of the oral tongue (SCCOT) is one of the most common malignant carcinomas in the head and neck. Recurrence and/or metastasis often results in failure of treatment and decreases the survival of the patients. The purpose of this study is to investigate the effect of gene-silence of Kif2a on SCCOT in viro and in vivo. STUDY DESIGN: Plasmid-mediated expression of Kif2a-siRNA (pGPU6/GFP/Kif2a) was employed to silence the expression of Kif2a in Tca8113 cells at both mRNA and protein levels. Tca8113 cell proliferation was measured by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and growth of Tca8113 tumors was determined by intra-tumor injection of pGPU6/GFP/Kif2a in nude mice. RESULTS: Gene-silence of Kif2a suppressed Tca8113 cell proliferation. pGPU6/GFP/Kif2a synergized the tumor suppression effect of 5-Fluorouracil (5-Fu) on Tca8113 cells. CONCLUSIONS: Our data support that Kif2a is a potential molecular target for the therapeutics of recurrent and metastatic SCCOT.