Immunohistochemical expression of MMP-9 and VEGF in squamous cell carcinoma of the tongue

Evaluation of Serum Levels of Matrix MetalloProteinase-9 (MMP-9) in Oral Squamous Cell Carcinoma and Its Clinicopathological Correlation

BACKGROUND

One of the most prevalent malignancies in India is oral squamous cell carcinoma (OSCC), which is found in more than 90% of cancer cases and has a reduced survival rate of 30%. Matrix metalloproteinases (MMPs) are zinc-containing and calcium-dependent endopeptidases that regulate angiogenesis, migration, and proliferation. MMP-9 in OSCC increases tumor progression through angiogenesis, degrades the basement membrane, and facilitates metastasis by changes in tissue shape. Its overexpression in OSCC has also been shown to have prognostic significance.

AIM

This study aims to evaluate the serum levels of MMP-9 in OSCC patients and healthy controls and to correlate with its clinicopathological staging.

MATERIALS AND METHODS

This study included 40 individuals; 20 patients with OSCC and 20 healthy controls. MMP-9 was determined in serum samples utilizing enzyme-linked immunosorbent assays.

RESULTS

 Descriptive statistics showed that 90% of the patients included in the OSCC groups were above 40 years, and 85% were males. There was a significant increase in the serum level of MMP-9 in OSCC patients compared to healthy controls with a mean difference of +28% (393.21 pg/ml) and a significant p-value of 0.001. (1365.80 ±236.414 pg/ml vs 973.67 ± 83.416 pg/ml). There was a significant increase in the serum levels of MMP-9 among the tumor stages and nodal involvement with a significant p-value of 0.002 and 0.001. No significant association was found between the age and gender groups in OSCC patients and serum levels of MMP-9.

CONCLUSION

 MMP-9 was significantly increased in OSCC when compared to healthy controls. Hence, MMP-9 can be used as a prognostic indicator in assessing tumor staging and nodal involvement.

Estimation of serum and salivary matrix metalloproteinase levels in oral squamous cell carcinoma patients: a systematic review and meta-analysis

Introduction

Matrix metalloproteinases (MMPs) play a pivotal role in the cancer progression, invasion, and angiogenesis.

Aim

This meta-analysis was conducted to evaluate the difference between oral squamous cell carcinoma (OSCC) patients and healthy controls in the serum and salivary MMP levels.

Material and methods

Four databases – Web of Science, PubMed, Scopus, and Cochrane Library – were searched up to March 2019. The pooled standard mean difference (SMD) and 95% confidence interval (CI) were obtained to explain the difference between the patients and controls in the salivary and serum MMP levels. Both Egger’s and Begg’s tests were considered as the significant publication bias.

Results

Thirteen case-control studies were included in the meta-analysis. Among the analyses of serum MMP levels, the serum MMP7 (SMD = 0.78; 95% CI: 0.15–1.41; p = 0.02) and MMP9 (SMD = 1.18; 95% CI: 0.51–1.84; p = 0.0005) levels were significantly higher in the OSCC patients than in the controls. In addition, the analyses of salivary MMP levels showed that the MMP1 (SMD = 0.46; 95% CI: 0.22–0.70; p = 0.0001) and MMP9 (SMD = 0.66; 95% CI: 0.19–1.12; p = 0.005) levels were significantly higher in the OSCC patients than in the controls.

Conclusions

The meta-analysis showed that the serum MMP7 and MPP9 levels as well as the salivary MMP1 and MPP9 levels were significantly higher in the OSCC patients than in the controls.

High expression of Rab31 confers a poor prognosis and enhances cell proliferation and invasion in oral squamous cell carcinoma

Dysregulation of Rab proteins has been observed in various types of cancer. Ectopic expression of Rab31, a member of the Rab protein family, is involved in cancer development and progression. However, the specific role and potential molecular mechanism underlying the functions of Rab31 remain largely unknown. Therefore, the current study aimed to investigate the functions of Rab31 in the development of cancer. Human oral squamous cell carcinoma (OSCC) samples were examined to determine the expression profile of Rab31 and its association with the clinicopathological characteristics of patients with OSCC. Knockdown of Rab31 expression with short hairpin RNA was performed to analyze the functions of Rab31 in vitro and in vivo. The expression of Rab31 was significantly elevated in human OSCC samples compared with that in normal oral mucosal epithelial tissues, and high expression levels were associated with high pathological grades. Furthermore, positive expression of Rab31 was associated with a poor prognosis in patients with OSCC. In addition, knockdown of Rab31 expression suppressed OSCC cell proliferation and induced apoptosis compared with those in the control‑transfected cells, which may have been caused by downregulated cyclin D1 and survivin expression and upregulated B‑cell lymphoma 2 expression. The invasive ability of OSCC cells was also abrogated by Rab31 silencing compared with that in the control‑transfected cells, which was associated with downregulated N‑cadherin and matrix metalloproteinase‑9 expression levels and upregulated levels of E‑cadherin expression. Furthermore, silencing Rab31 in OSCC cell lines, when compared with the control‑transfected cells, significantly reduced tumor growth and inhibited the expression of survivin, Ki‑67 and N‑cadherin in vivo. By contrast, the expression levels of E‑cadherin were increased. Taken together, the results of the present study supported important roles for Rab31 in regulating OSCC cell proliferation, apoptosis and invasion and may facilitate the identification of a new therapeutic target for the treatment of OSCC.

EXPRESSION OF MATRIX METALLOPROTEINASE-9 IN ORAL SQUAMOUS CELL CARCINOMA AND ORAL PSEUDOEPITHELIOMATOUS HYPERPLASIA

Background: Oral pseudoepitheliomatous hyperplasia (PEH) appears histologically similar to oral squamous cell carcinoma (OSCC) in small oral biopsies, thus posing diagnostic dilemma. The objective of this study was to compare the expression of matrix metalloproteinase-9 (MMP-9) in differential diagnosis of OSSC and oral PEH. Materials & Methods: This comparative cross-sectional study was conducted in the Department of Histopathology, Armed Forces Institute of Pathology (AFIP), Rawalpindi, Pakistan from January 2013 to March 2016. It included sixty archival cases, 30 each of OSCC and PEH. Paraffin embedded blocks were prepared, hematoxylin and eosin stained sections taken and immunostained with MMP-9. The expression of MMP-9 was evaluated in OSCC and PEH. Results: The OSCC group included 16 (53.33%) men and 14 (46.67%) women, whereas PEH group included 18 (60%) men and 12 (40%) women. The mean age of OSCC group was 60.1±17.3 and that of PEH group was 52.7±16.6. In OSCC group, site of lesion was buccal mucosa in 12 (40%), gingiva 10 (33.33%), tongue 7 (23.33%) and floor of mouth 1 (3.34%) case. In PEH group, site of lesion was buccal mucosa in 12 (40%), tongue 11 (36.66%), gingiva 6 (20%) and palate 1 (3.34%) case. The expression of MMP-9 was positive in all the 30 cases of OSCC and negative in all 30 cases of PEH. Conclusion: Compared to pseudoepitheliomatous hyperplasia (PEH), MMP-9 revealed a higher expression in oral squamous cell carcinoma (OSCC). This finding has become mainstream strategy in distinguishing OSCC from PEH in oral mucosal biopsies in cases difficult to diagnose.

Salivary MMP-9 as a Biomarker for the Diagnosis of Oral Potentially Malignant Disorders and Oral Squamous Cell Carcinoma

OBJECTIVE

To compare the salivary MMP - 9 concentration among subjects with oral squamous cell carcinoma (OSCC), oral potentially malignant disorders (OPMD), tobacco users, and control groups.

MATERIALS AND METHODS

A total of 88 subjects were enrolled and divided into four study groups viz., OSCC (n=24), OPMD (n=20), tobacco habits (n=22), and healthy controls (n=22). All subjects gave unstimulated saliva samples for the evaluation MMP - 9 by ELISA kit. Demographic information like age, gender, type of tobacco, and duration of the habit were recorded.

RESULTS

Subjects with OSCC and OPMD had significantly higher mean MMP-9 levels than subjects with tobacco habits and control groups (P<0.001). Also, poorly differentiated OSCC group had significantly higher mean saliva MMP-9 than moderate and well-differentiated OSCC. The optimal cut-off point was 214.37 ng/mL with a sensitivity of 100% and specificity of 59% for OSCC versus the control group. The optimal cut-off point was as 205.87 ng/mL with a sensitivity of 100% and a specificity of 54% for OPMD versus the control group.

CONCLUSION

The data obtained from this study indicated that OSCC and OPMD had an increased level of salivary MMP-9. Salivary MMP-9 could be a useful, non-invasive adjunct technique in the diagnosis, treatment, and follow-up of OSCC and OPMD. <br />.

Association between immunohistochemical expression of matrix metalloproteinases and metastasis in oral squamous cell carcinoma: Systematic review and meta-analysis

BACKGROUND

The aim of this systematic review (SR) was to summarize and critically appraise available evidence on the association of the immunohistochemical expression of matrix metalloproteinases (MMPs) with the occurrence of lymph node/distant metastasis of oral squamous cell carcinoma (OSCC).

METHODS

Searches were conducted in five main electronic and three gray literature databases.

RESULTS

From 2128 records identified, 50 were included for qualitative analysis. A total of 12 MMPs were identified (-1, -2, -3, -7, -8, -9, -10, -11, -13, -25, -26, and MT1-MMP). Most included studies reported a positive association of MMP-1, -2, -3, -7, -9, and MT1-MMP with lymph node metastasis. MMP-8, -25, and -26 were not associated with lymph node metastasis.

CONCLUSIONS

According to this SR, MMP-1, -2, -3, -7, -9, and MT1-MMP seem to play an important role in lymph node metastasis of OSCC.

Induction of ALP and MMP9 activity facilitates invasive behavior in heterogeneous human BMSC and HNSCC 3D spheroids

Mesenchymal stem cells (MSCs) are multipotent progenitor cells capable of differentiating into adipocytic, osteogenic, chondrogenic, and myogenic lineages. There is growing evidence that MSCs home into the tumor microenvironment attracted by a variety of signals such as chemokines, growth factors, and cytokines. Tumor-homing stem cells may originate from bone marrow-derived MSCs (BMSCs) or adipose tissue-derived MSCs. Recent scientific data suggest that MSCs in combination with tumor cells can either promote or inhibit tumorigenic behavior. In head and neck squamous cell carcinoma (HNSCC), BMSCs are reported to be enriched with a potential negative role. Here, we evaluated the effect of BMSCs from 4 different donors in combination with 4 HNSCC cell lines in a 3-dimensional multicellular spheroid model. Heterogeneous combinations revealed an up-regulation of gene and protein expression of osteogenic markers runt-related transcription factor 2 (RUNX2) and alkaline phosphatase (ALP) together with a substantial secretion of matrix metalloproteinase 9. Moreover, heterogenous BMSC/tumor spheroids showed increased invasion compared with homogenous spheroids in a Boyden chamber invasion assay. Furthermore, inhibition of ALP resulted in a substantially decreased spreading of heterogeneous spheroids on laminin-rich matrix. In summary, our data suggest a prometastatic effect of BMSCs combined with HNSCC.-Wessely, A., Waltera, A., Reichert, T. E., Stöckl, S., Grässel, S., Bauer, R. J. Induction of ALP and MMP9 activity facilitates invasive behavior in heterogeneous human BMSC and HNSCC 3D-spheroids.

Effects of peritumoral bevacizumab injection against oral squamous cell carcinoma in a nude mouse xenograft model: A preliminary study

Angiogenesis serves a crucial role in tumor growth. Vascular endothelial growth factor (VEGF) is a potent regulator of tumor angiogenesis and is highly expressed in oral squamous cell carcinoma (OSCC). Bevacizumab, which binds to VEGF-A, inhibits the biological activity of VEGF and is clinically administered by intravenous injection. As intravenous chemotherapy intensifies the side effects experienced by OSCC patients, an alternative treatment option is desirable, particularly for older patients with OSCC who present with systemic disease complications. Generally, local injections of antitumor agents enhance tumoricidal activity and decrease side effects. However, the antitumor effects of peritumoral bevacizumab injections in OSCC are not fully understood. Therefore, the present study examined the effects of peritumoral bevacizumab injections in an experimental nude mouse model of OSCC through immunohistochemical staining for cluster of differentiation (CD)31 and α-smooth muscle actin (α-SMA) and apoptosis assays. It was identified that peritumoral injections of bevacizumab significantly inhibited tumor growth in OSCC xenografts compared with peritumoral saline injections or no treatment (controls), and it was also revealed that treatment with bevacizumab significantly reduced CD31- and α-SMA-positive microvessel density (P<0.01) and increased level of tumor cell apoptosis (P<0.01) compared with the controls. In conclusion, these results collectively support the experimental basis for the clinical development of peritumoral bevacizumab injections for the treatment of OSCC.

GROWTH FACTORS AND COX2 IN WOUND HEALING: AN EXPERIMENTAL STUDY WITH EHRLICH TUMORS

Background

Healing is an innate biological phenomenon, and carcinogenesis acquired, but with common humoral and cellular elements. Carcinogenesis interferes negatively in healing.

Aim

To evaluate the histological changes in laparotomy scars of healthy Balb/c mice and with an Ehrlich tumor in its various forms of presentation.

Methods

Fifty-four mice were divided into three groups of 18 animals. First group was the control; the second had Ehrlich tumor with ascites; and the third had the subcutaneous form of this tumor. Seven days after tumor inoculation, all 54 mice were submitted to laparotomy. All of the animals in the experiment were operated on again on 7th day after surgery, with resection of the scar and subsequent euthanasia of the animal. The scars were sent for histological assessment using immunohistochemical techniques to evaluate Cox-2 (cyclooxygenase 2), VEGF (vascular endothelial growth factor) and FGF (fibroblast growth factor). Semi-quantitatively analysis was done in the laparotomy scars and in the abdominal walls far away from the site of the operation.

Results

Assessing the weight of the animals, the correct inoculation of the tumor and weight gain in the group with tumoral ascites was observed. The histological studies showed that groups with the tumor showed a statistically significant higher presence of Cox-2 compared to the control. In the Cox-2 analysis of the abdominal wall, the ascites group showed the most significant difference. VEGF did not present any significant differences between the three groups, regardless of the site. The FGF showed a significant increase in animals with the tumor.

Conclusion

Histological findings in both laparotomy scar and the abdominal wall showed that with Ehrlich's neoplasia there was an exacerbated inflammatory response, translated by more intense expression of Cox-2 and greater fibroblast proliferation, translated by more intense expression of FGF, that is, it stimulated both the immediate inflammatory reactions, observed with Cox-2 reactions, and late scarring by fibroblasts and FGF.

Expression of Matrix Metalloproteinase-10 at Invasive Front of Squamous Cell Carcinoma and Verrucous Carcinoma in the Oral Cavity

BACKGROUND

Matrix metalloproteinases (MMPs) are a family of zinc metalloproteinases capable of degrading components of connective tissues. MMP-10 is frequently expressed in human cancers. The aim of this study was to immunohistochemically evaluate its expression in oral squamous cell carcinoma (OSCC) and verrucous carcinoma (OVC).

MATERIALS AND METHODS

A retrospective analysis of 73 samples (31 OSCC, 22 OVC and 20 non-neoplastic epithelium) was performed. All samples were immunohistochemically stained with monoclonal MMP-10 antibody and expression levels and staining intensity were evaluated with respect to microscopic features. Data were analyzed by SPSS (V.21), Mann-Whitney and Kruskal Wallis tests.

RESULTS

MMP-10 was detected in all OSCC and OVC cases. The expression of MMP-10 in OSCC was intensive (score 3) and in OVC was low and moderate (score 1 and score 2) more frequently. Non- neoplastic epithelium did not show MMP-10 expression. Differences between groups was statistically significant (p<0.05). However, the expression of MMP- 10 was not obviously different between various grades of OSCC.

CONCLUSIONS

According to our study, MMP-10 protein can be important possible factor in the transformation of normal oral epithelium to OVC and OSCC, also the level of MMP-10 expression at invasion front of the lesions can be helpful in the differentiation of OVC and OSCC.

Knocking down of p53 triggers apoptosis and autophagy, concomitantly with inhibition of migration on SSC-4 oral squamous carcinoma cells

Oral squamous cell carcinoma (OSCC) is a malignancy with elevated prevalence and somber prognosis due to the fact that most of the patients are diagnosed at an advanced stage. p53 has a crucial role in proliferation and apoptosis during the occurrence and development of numerous malignant tumors. The impact of mutated p53 on the development and progression of OSCC is unclear and might have therapeutic implications. Using an in vitro RNA interference experiment, we have evaluated the impact of p53 knockdown on cell viability, apoptosis, migration, and gene expression for key genes involved in apoptosis and angiogenesis. We observed that inhibiting the expression of p53 decreased the proliferation ability and induced apoptosis/autophagy in SSC-4 cells. Moreover, we observed that this has decreased migration and has blocked the expression of VEGF. In conclusion, our research provides a proof that a direct connection between p53 knockdown and OSCC cell death can be established, therefore opening new potential directions in OSCC molecular therapeutics and management.

AMPK-dependent signaling modulates the suppression of invasion and migration by fenofibrate in CAL 27 oral cancer cells through NF-κB pathway

Fenofibrate, a peroxisome proliferator-activated receptor alpha (PPARα) agonist and lipid-lowering agent, has been used worldwide for treatment of hyperlipidemia. The clinical trials demonstrate that fenofibrate possesses multiple pharmacological activities, including antitumor effects. However, the precise mechanisms in oral squamous cell carcinoma (OSCC) remain unclear. In this study, we investigated the anticancer effects of fenofibrate on the migration and invasion of human oral cancer CAL 27 cells. Fenofibrate inhibited the cell migration and invasion of CAL 27 cells by the wound healing and Boyden chamber transwell assays, respectively. In addition, fenofibrate reduced the protein expressions of MMP-1, MMP-2, MMP-7, and MMP-9 by Western blotting and inhibited enzyme activities of MMP-2/-9 using gelatin zymography assay. Results from immunoblotting analysis showed that the proteins of p-LKB1 (Ser428), LKB1, p-AMPKα (Thr172), p-AMPKα1/α2 (Ser425/Ser491), p-AMPKβ1 (Ser108), and AMPKγ1 were upregulated by fenofibrate; the levels of p-IKKα/β (Ser176) and p-IκBα were reduced in fenofibrate-treated cells. Also, fenofibrate suppressed the expressions of nuclear NF-κB p65 and p50 by immunoblotting and NF-κB DNA binding activity by EMSA assay. The anti-invasive effect of fenofibrate was attenuated by compound C [an adenosine 5'-monophosphate-activated protein kinase (AMPK) inhibitor] or dominant negative form of AMPK (DN-AMPKα1). Thus, fenofibrate considerably inhibited metastatic behaviors of CAL 27 cells might be mediated through blocking NF-κB signaling, resulting in the inhibition of MMPs; these effects were AMPK-dependent rather than PPARα signaling. Our findings provide a molecular rationale, whereby fenofibrate exerts anticancer effects and additional beneficial effects for the treatment of cancer patients. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 866-876, 2016.

Serum and salivary levels of chemerin and MMP-9 in oral squamous cell carcinoma and oral premalignant lesions

OBJECTIVE

The objective of this study was to investigate serum and salivary levels of chemerin and MMP-9 as early diagnostic biomarkers for patients with oral premalignant lesions (OPMLs) and oral squamous cell carcinoma (OSCC).

METHODS

This study included 45 individuals; 15 healthy control, 15 patients with OPMLs, and 15 patients with early stage OSCC. Chemerin and MMP-9 were determined in serum and saliva samples utilizing enzyme-linked immunosorbent assays.

RESULTS

Serum and salivary levels of chemerin and MMP-9 in patients with OSCC were significantly higher than OPMLs and control group. Patients with OPMLs showed also elevated profiles for serum and salivary chemerin and MMP-9 compared to control group. Receiver operator characteristic curve analysis revealed that all tested biomarkers have 100 % sensitivity and 100 % specificity with area under the curve (AUC) of 1.00 in detecting early stage OSCC and OPMLs. In distinguishing OSCC from OPMLs, salivary MMP-9, serum chemerin, and salivary chemerin showed AUC of 0.99, 0.92, and 0.88, respectively, showing higher sensitivity and specificity compared with serum MMP-9 (AUC; 0.6) which failed to differentiate between the two conditions.

CONCLUSION

Chemerin and MMP-9 might be considered as salivary diagnostic biomarkers for OPMLs and early detection of OSCC and also for detecting early cancerization of OPMLs.

CLINICAL RELEVANCE

This research implied that salivary chemerin was a novel diagnostic factor for patients with OPML and early stage OSCC patients, and chemerin could be a new therapeutic target for regulating cancer angiogenesis and blocking malignization of OPMLs.

Clinical Significance and Roles in Angiogenesis of Circulating Microparticles in Oral Cancer

Our recent study established the increased circulating microparticles (MPs) and their procoagulant activity in oral squamous cell carcinoma (OSCC). In the present study, we further evaluated different phenotypes of circulating MPs in OSCC patients and explored their clinical significance and effects on angiogenesis (a critical event in tumor progression). To conduct the study, circulating MPs in 45 OSCC patients and 18 healthy volunteers were characterized and quantified by transmission electron microscopy and flow cytometry. Correlations between circulating MPs and clinicopathologic data, microvessel density, and proangiogenic factor levels in patients with OSCC were analyzed by immunohistochemistry and Spearman rank correlation test. Additionally, the in vitro studies were performed with use of human umbilical vein endothelial cells. Our results showed that the levels of circulating MPs as well as the subsets of platelet-derived, endothelium-derived, and pan-leukocyte MPs in stages III to IV OSCC were significantly higher than stages I to II and healthy subjects. Moreover, these increased circulating MPs were significantly correlated with tumor size, TNM stages, microvessel density, and expression levels of vascular endothelial growth factor (VEGF) and matrix metallopeptidase 9 (MMP9) in OSCC patients. The in vitro studies revealed that circulating MPs isolated from OSCC patients could be effectively taken up by human umbilical vein endothelial cells and could promote the proliferation, migration, invasion, and tube formation of recipient endothelial cells, accompanied by increased expression of proangiogenic factors. In summary, circulating MPs play important roles in angiogenesis and local tumor progression of OSCC. Our results shed new light on the progression of OSCC and might be helpful to explore novel treatment strategies targeting tumor angiogenesis.

Prognostic significance of CD44v6, p63, podoplanin and MMP-9 in oral squamous cell carcinomas

OBJECTIVES

To analyse the expression of the CD44v6, p63, podoplanin and MMP-9, and their prognostic significance in patients with oral squamous cell carcinomas (OSCC).

MATERIAL AND METHODS

Immunohistochemistry technique was performed on 60 OSCC for detection of CD44v6, p63, podoplanin and MMP-9 proteins. Extent and intensity of staining were evaluated in tumour cells and were compared with patients' clinical-pathological characteristics and survival.

RESULTS

CD44v6 expression was detected at the membrane of tumour cells of 94% cases. Nuclear expression of p63 protein was present in 96.5%. Podoplanin was observed at the membrane of tumour cells of 94% cases. MMP-9 was found in the cytoplasm of tumour cells in 83.7% cases. A high level of expression (67%-89%) in all four proteins was noted. Podoplanin was associated with the expression of MMP-9 (P = 0.010) and both were associated with lymph node metastasis (P = 0.011 and P = 0.018, respectively). Co-expression of podoplanin/MMP-9 was an adverse independent prognostic factor for cancer-specific survival (P = 0.008) and recurrence-free survival (P = 0.042).

CONCLUSION

Podoplanin and MMP-9 together could contribute to tumour progression and dissemination of OSCC. Their combined overexpression showed an adverse effect on survival, suggesting that they could be regarded as important prognostic biomarkers in OSCC.

Cyclin D1 and Ki-67 expression correlates to tumor staging in tongue squamous cell carcinoma

BACKGROUND

The immunohistochemical expression of Cyclin D1 and Ki-67 were analyzed in tongue squamous cell carcinomas (SCC), relating them to the clinical and morphological exhibition of these tumors.

MATERIAL AND METHODS

Twenty-nine patients fulfilled the inclusion criteria; clinical data included gender, age, ethnicity and use of licit drugs such as alcohol and tobacco. The TNM staging and histopathological differentiation grading was assessed for each case. In addition, T1 patients were gathered with T2 patients; and T3 patients were gathered with T4 patients to assemble two distinct groups: (T1/T2) and (T3/T4).

RESULTS

The mean follow-up time was 24 months and 30% of the patients died as a consequence of the disease, while 23.3% lived with the disease and 46.7% lived lesion-free. T1 and T2 tumors showed statistically lesser Ki-67 and Cyclin D1 staining when compared to T3 and T4 tumors.

CONCLUSIONS

Ki-67 and Cyclin D1 pose as auxiliary tools when determining the progression of tongue SCC at the time of diagnosis.

Frizzled2 mediates the migration and invasion of human oral squamous cell carcinoma cells through the regulation of the signal transducer and activator of transcription-3 signaling pathway

Frizzled2 (Fzd2) is a receptor for wingless-type MMTV integration site family members (Wnts), the aberrant overexpression of which has been noted to contribute to cancer metastasis. The present study was performed to characterize the role of Fzd2 in the migration and invasion of oral squamous cell carcinomas (OSCC) in vitro. Using TSCCa cells (a tongue SCC cell line) for loss- or gain-of-function of Fzd2, we found that a forced overexpression of Fzd2 promoted TSCCa cell migration and invasion, decreased the expression of epithelial‑cadherin (E-cadherin, an epithelial marker) and increased that of vimentin, Snail Slug, matrix metalloproteinases (MMPs)-2/-9/-13 and a-disintegrin and metalloproteinase with thrombospondin motifs-5 (ADAMTS5). By contrast, RNA interference (RNAi)-mediated knockdown of Fzd2 had opposite effects on OSCC cells. In addition, we found that the phosphorylation of signal transducer and activator of transcription-3 (STAT3) was enhanced by Fzd2 overexpression, but suppressed by Fzd2 depletion, and that STAT3‑specific shRNA attenuated Fzd2 overexpression‑induced cell invasion. In summary, the present study demonstrated that Fzd2 contributes to the migration and invasion of OSCC cells, at least partly through regulation of the STAT3 pathway. These results suggest Fzd2 as a novel therapeutic target for OSCC.

Application value of MRI combined with positron emission tomography (PET)/CT in diagnosis and preoperative staging of tongue squamous cell carcinoma

INTRODUCTION

This study aimed to compare and analyse the findings of tongue squamous cell carcinoma (TSCC) on MRI and positron emission tomography (PET)/CT and explore the diagnostic utility of combined MRI-PET/CT in the diagnosis and preoperative staging of TSCC.

METHODS

A prospective analysis of MRI and PET/CT data in 18 TSCC cases was performed. Cases were comprehensively staged on MRI and PET/CT preoperatively according to American Joint Committee on Cancer (AJCC) staging criteria and confirmed by pathological results.

RESULTS

The highest and lowest sensitivities of preoperative AJCC staging I-IV using MRI alone, PET/CT alone and combined MRI-PET/CT were 100.0%, 100.0% and 100.0% (stage II) and 50.4%, 55.6% and 55.6% (stage I), respectively. The highest specificities were 100.0%, 100.0% and 100.0% (stage II), and the highest correct rates were 100.0%, 96.5% and 100.0% (stage II). Compared with the postoperative pathological staging, preoperative staging showed no significant difference for stages I-II and IV (P > 0.05); however, stage III showed a significant difference (P < 0.05). When combined MRI-PET/CT was compared with MRI alone in the accuracy of preoperative TSCC staging, there was no significant difference for stages I-III (P > 0.05), but there was a significant difference for stage IV (P < 0.05).

CONCLUSIONS

Combined MRI and PET/CT could serve as an important tool for the accurate diagnosis and preoperative staging of TSCC and could improve the accuracy of preoperative TSCC staging.

Curcumin synergistically enhances the radiosensitivity of human oral squamous cell carcinoma via suppression of radiation-induced NF-κB activity

The anticancer effect of curcumin has been widely reported. However, whether curcumin can enhance the radiosensitivity of human oral squamous cell carcinoma (OSCC) remains to be elucidated. The aim of the present study was to evaluate the efficacy of curcumin combined with radiation against OSCC. SAS cells were transfected with the luciferase gene (luc) and named SAS/luc. NF-κB/DNA binding activity, the surviving fraction and NF-κB-regulated effector protein expression were determined by electrophoretic mobility shift assay, clonogenic survival assay and western blotting, respectively. The therapeutic efficacy was evaluated in SAS/luc tumor-bearing mice by caliper measurement and bioluminescence imaging. Curcumin enhanced SAS/luc radiosensitivity through the inhibition of radiation-induced NF-κB activity and expression of effector proteins both in vitro and in vivo. With 4 Gy or greater radiation doses, synergistic effects of curcumin were observed. The combination group (curcumin plus radiation) had significantly better tumor control compared with that of curcumin or radiation alone. No significant body weight change of mice was found throughout the entire study. In conclusion, curcumin is a radiosensitizer against OSCC with negligible toxicity.

Collagen XVI induces expression of MMP9 via modulation of AP-1 transcription factors and facilitates invasion of oral squamous cell carcinoma

Collagen XVI belongs to the family of fibril-associated collagens with interrupted triple helices (FACIT). It is overexpressed during the progression of oral squamous cell carcinoma (OSCC). The present data show a strong collagen XVI-dependent induction of MMP9 and an increase in OSCC cell invasion. We found activated integrin-linked kinase (ILK) in a complex with kindlin-1 and activation of protein kinase B (PKB/Akt) to be responsible for MMP9 induction. Inhibition of the formation of focal adhesions reduced MMP9 expression. Moreover, collagen XVI overexpressing OSCC cell clones (COLXVI cell clones) transfected with vectors containing different MMP9 promoter fragments adjacent to a luciferase reporter revealed an increase in luciferase signal dependent on AP-1 binding sites. Deletion of the AP-1 binding site 98 bp upstream of the reported transcription start site and inhibition of AP-1 with Tanshinone IIA resulted in decreased MMP9 expression. The AP-1 subunit JunB showed differential expression between COLXVI cell clones and mock control cells. Additionally, mass spectrometric analysis of immunoprecipitates revealed that c-Fos interacted strongly with dyskerin in COLXVI cell clones compared to mock controls.

Fluctuating roles of matrix metalloproteinase-9 in oral squamous cell carcinoma

One hallmark of cancer is the degradation of the extracellular matrix (ECM), which is caused by proteinases. In oral cancers, matrix metalloproteinases (MMPs), especially MMP-9, are associated with this degradation. MMPs break down the ECM allowing cancer to spread; they also release various factors from their cryptic sites, including cytokines. These factors modulate cell behavior and enhance cancer progression by regulating angiogenesis, migration, proliferation, and invasion. The development of early metastases is typical for oral cancer, and increased MMP-9 expression is associated with a poor disease prognosis. However, many studies fail to relate MMP-9 expression with metastasis formation. Contrary to earlier models, recent studies show that MMP-9 plays a protective role in oral cancers. Therefore, the role of MMP-9 is complicated and may fluctuate throughout the different types and stages of oral cancers.