Angiogenesis In Oral Squamous Cell Carcinoma Research Articles

MEG3-Mediated Oral Squamous-Cell-Carcinoma-Derived Exosomal miR-421 Activates Angiogenesis by Targeting HS2ST1 in Vascular Endothelial Cells.

Exosomal microRNAs (miRNAs) from cancer cells play a key role in mediating the oral squamous cell carcinoma (OSCC) microenvironment. The objective of this study was to investigate how the long non-coding RNA (lncRNA) MEG3 affects OSCC angiogenesis through exosomal miR-421. Global miRNA microarray analysis and quantitative real-time PCR (qRT-PCR) were performed to determine the level of miRNAs in OSCC cell-derived exosomes. Cell migration, invasion, tube formation, immunohistochemistry, and hemoglobin concentrations were used to study the effects of exosomal miR-421 in angiogenesis. Western blotting was used to determine the expression level of HS2ST1 and VEGFR2-related downstream proteins. MiRNA array and qRT-PCR identified the upregulation of miR-421 in OSCC cell-derived exosomes. Furthermore, exosomal miR-421 can be taken up by human umbilical vein endothelial cells (HUVECs) and then target HS2ST1 through VEGF-mediated ERK and AKT phosphorylation, thereby promoting HUVEC migration, invasion, and tube formation. Additionally, forced expression of the lncRNA MEG3 in OSCC cells reduced exosomal miR-421 levels and then increased HS2ST1 expression, thereby reducing the VEGF/VEGFR2 pathway in HUVECs. Our results demonstrate a novel mechanism by which lncRNA MEG3 can act as a tumor suppressor and regulate endothelial angiogenesis through the exosomal miR-421/HS2ST1 axis, which provides a potential therapeutic strategy for OSCC angiogenesis.

Hypoxia-induced tumor exosomes promote angiogenesis through miR-1825/TSC2/mTOR axis in oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) is characterized by enhanced angiogenesis resulting in poor prognosis despite improvements in diagnostic/therapeutic techniques. Here, we aimed at investigating potential roles of miR-1825 enclosed in OSCC-derived exosomes on angiogenesis under hypoxic conditions. Effects of miR-1825 mimic/inhibitor as well as hypoxia-induced tumor derived exosomes on human umbilical vein endothelial cells (HUVECs) were evaluated using cell viability, migration/invasion, tube formation, and spheroid-based 3D angiogenesis assays. Hypoxic conditions caused significant increase in miR-1825 levels in OSCC cells and hiTDEs. miR-1825 alone and within hiTDEs promoted endothelial cell viability, migration, invasion, and angiogenic potential, which is reversed via inhibition of miR-1825 expression. miR-1825 within hiTDEs altered the angiogenesis potential of HUVEC cells via deregulation of TSC2/mTOR axis. We showed that hypoxia led to OSCC-derived exosome mediated transfer of miR-1825 to HUVECs and enhanced angiogenesis in OSCC in vitro.

Combination Treatment of TRPV4 Agonist with Cisplatin Promotes Vessel Normalization in an Animal Model of Oral Squamous Cell Carcinoma.

Background and Objectives: Oral squamous cell carcinoma (OSCC) is the sixth most common malignancy in the world. Transient receptor potential vanilloid 4 (TRPV4) channel has been shown to be involved in angiogenesis in multiple types of tumors. However, not much is known about TRPV4′s involvement in OSCC. Thus, in this study, we investigate the effect of administering a TRPV4 agonist on angiogenesis in OSCC. Materials and Methods: Thirty-six Sprague Dawley (SD) rats were used in this study. 4-nitroquinoline 1-oxide (4NQO) was used to induce OSCC. Cisplatin (an anticancer drug), and GSK1016790A (an agonist for TRPV4) was used in this study. Immunohistochemistry was employed to examine the TRPV4 expression. An RT2 Profiler PCR Array was performed for gene expression analysis of TRPV4, vascular growth factors that correspond directly with angiogenesis, such as angiopoietin (Ang-1 and Ang-2), and tyrosine kinase (Tie-1 and Tie-2) receptors. Tumor vessel maturity was assessed by microvessel density and microvessel-pericyte-coverage index. Results: RT2 profiler PCR array showed significant elevated levels of Ang-1 (2.1-fold change; p < 0.05) and Tie-2 (4.5-fold change; p < 0.05) in OSCC following the administration of a combination of GSK1016790A and cisplatin. Additionally, the combination treatment significantly reduced the microvessel density (p < 0.01) and significantly increased the percentage of microvessels covered with pericytes (p < 0.01) in OSCC. Furthermore, tumor size was significantly reduced (p < 0.05) in rats that received cisplatin alone. The combination treatment also greatly reduced the tumor size; however, the data were not statistically significant. Conclusions: The findings suggest that combining a TRPV4 agonist with cisplatin for treatment of OSCC promote vessels normalization via modulation of Ang-1/Tie-2 pathway.

Expression of CD44 (NKI-P1) in oral squamous cell carcinoma associated vascular endothelial cells: A relationship to tumor angiogenesis

BackgroundOral squamous cell carcinoma is characterized by high degree of local invasion with metastasis as well as characteristic angiogenic features. Angiogenesis is a critical step in the growth and metastasis of tumors. Cluster of differentiation 44 (CD44) is a cell surface glycoprotein which is widely expressed in both physiological and pathological conditions. AimThe study was designed to assess the expression of CD44 (NKI-P1) in oral squamous cell carcinoma associated endothelial cells and to correlate this expression with matrix metalloprpteinase-9 (MMP-9) and transforming growth factor-beta (TGF- β) expression immunohistochemically. Materials and methodsOne hundred fourteen archival oral squamous cell carcinoma cases were used in this study. Immunohistochemistry was performed for CD44 (NKI-P1), Ki-67, cluster of differentiation 31(CD31), podoplanin (D2-40), MMP-9 and TGF- β. Microvessel density was also determined morphologically. Results: CD44 was expressed in (CD31+/ Podoplanin –) blood vascular endothelial cells in a strong cytoplasmic fashion. In addition, the extracellular matrix proteins (MMP-9 and TGF-β were expressed in oral squamous cell carcinoma stroma which was enriched with CD44 + blood vessels. The mean numbers of microvessel density in connective tissue beneath normal epithelium and different grades of oral squamous cell carcinoma stroma were 5.8, 22.1, 22.4 and 23.5, respectively with the P-value < 0.05, where a significant statistical difference between microvessel density in the connective tissue beneath normal epithelia and stroma of all grades of oral squamous cell carcinoma was found. Conclusion: CD44 (NKI-P1) is considered a potential marker of oral squamous cell carcinoma angiogenesis and it can be used as a valuable biomarker of tumor invasion and as a therapeutic target for anti-angiogenic therapies.

LncRNA FENDRR in Carcinoma-Associated Fibroblasts Regulates the Angiogenesis of Oral Squamous Cell Carcinoma Through the PI3K/AKT Pathway.

Angiogenesis is essential for the development of tumors. Studies have shown that carcinoma-associated fibroblasts (CAFs) are involved in regulating tumor angiogenesis, but the mechanism remains unclear. Recently, long noncoding RNAs (lncRNAs) have been proved to play an important role in the angiogenesis of various tumors. However, there is currently no research involving the regulation of CAFs on the angiogenesis of oral squamous cell carcinoma (OSCC) mediated by lncRNAs. By analyzing microarray data, we identified that the expression of lncRNA FOXF1 adjacent noncoding developmental regulatory RNA (FENDRR) in OSCC patients is downregulated, compared to that in normal tissues. Quantitative polymerase chain reaction (qPCR) results demonstrated that FENDRR expression is lower in CAFs compared to normal fibroblasts (NFs) of OSCC patients. KEGG pathway analysis revealed that some genes differentially expressed between CAFs and NFs of HNSCC patients are enriched to the PI3K/AKT pathway. Further experiments confirmed that the downregulation of FENDRR can activate the PI3K/AKT pathway in NFs and enhances the expression of matrix metalloproteinase 9 (MMP9). The overexpression of FENDRR had the opposite effect. Besides, we co-cultured human umbilical vein endothelial cells (HUVECs) with CAFs, and the tube-forming ability of HUVECs co-cultured with CAFs overexpressing FENDRR decreased significantly. However, activation of the AKT pathway of CAFs overexpressing FENDRR can weaken the inhibitory effect of FENDRR on angiogenesis. In summary, our experiments are focused on the influence of lncRNAs in CAFs on OSCC angiogenesis for the first time and prove that FENDRR mediates CAFs’ regulation of OSCC angiogenesis through the PI3K/AKT pathway.

Monocyte Chemoattractant Protein 1 Promotes VEGF-A Expression in OSCC by Activating ILK and MEK1/2 Signaling and Downregulating miR-29c.

Oral squamous cell carcinoma (OSCC) is an aggressive tumor that has a poor prognosis, with high levels of local invasion and lymph node metastasis. Vascular endothelial growth factor A (VEGF-A) plays essential roles in OSCC tumor angiogenesis and metastasis. Monocyte chemoattractant protein-1 (MCP-1, CCL2) is implicated in various inflammatory conditions and pathological processes, including oral cancer. The existing evidence has failed to confirm any correlation between MCP-1 or VEGF-A expression and OSCC angiogenesis. In this study, high expression levels of MCP-1 and VEGF-A were positively correlated with disease stage in patients with OSCC. In oral cancer cells, MCP-1 increased VEGF-A expression and subsequently promoted angiogenesis; miR-29c mimic reversed MCP-1 activity. We also found that MCP-1 modulated VEGF-A expression and angiogenesis through CCR2/ILK/MEK1/2 signaling. Ex vivo results of the chick embryo chorioallantoic membrane (CAM) assay revealed the angiogenic qualities of MCP-1, with increased numbers of visible blood vessel branches. Our data suggest that MCP-1 is a new molecular therapeutic target for the inhibition of angiogenesis and metastasis in OSCC.

Abstract 1480: CCL4 promotes oral squamous cell carcinoma angiogenesis by targeting the angiopoietin-2 signal pathway

Abstract The inflammatory chemokine (C-C motif) ligand 4 (CCL4) plays an important role in the pathogenesis and progression of cancer, with higher serum CCL4 levels in patients with oral squamous cell carcinoma (OSCC) marking a more advanced stage of disease. OSCC accounts for approximately 95% of oral cancer in Taiwan and this disease has a poor prognosis, with aggressive local invasion and metastasis predisposing to recurrence and additional morbidity. Angiogenesis, a physiological process that enables new blood vessels to form from pre-existing vessels, is involved in the growth, maintenance, and metastasis of most tumors. Angiopoietin-2 (ANGPT2) induces angiogenesis and is a potent endothelial cell-specific mitogen. Until now, it has been unclear as to whether levels of CCL4 expression are a marker of angiogenic activity in patients with OSCC and are correlated with higher levels of ANGPT2 expression. Our investigations have found that treating OSCC cells with CCL4 increases ANGPT2 expression and that CCL4 treatment promotes angiogenesis in a murine model of OSCC. Thus, CCL4 may be a novel molecular therapeutic target for inhibiting angiogenesis and metastasis in OSCC. Citation Format: Ming-Yu Lien. CCL4 promotes oral squamous cell carcinoma angiogenesis by targeting the angiopoietin-2 signal pathway [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1480.

Activin A triggers angiogenesis via regulation of VEGFA and its overexpression is associated with poor prognosis of oral squamous cell carcinoma.

Poor prognosis associated with the dysregulated expression of activin A in a number of malignancies has been related to with numerous aspects of tumorigenesis, including angiogenesis. The present study investigated the prognostic significance of activin A immunoexpression in blood vessels and cancer cells in a number of oral squamous cell carcinoma(OSCC) cases and applied invitro strategies to determine the impact of activin A on angiogenesis. In a cohort of 95 patients with OSCC, immunoexpression of activin A in both blood vessels and tumor cells was quantified and the association with clinicopathological parameters and survival was analyzed. Effects of activin A on the tube formation, proliferation and migration of human umbilical vein endothelial cells(HUVECs) were evaluated in gain‑of‑function (treatment with recombinant activin A) or loss‑of‑function [treatment with activin A‑antagonist follistatin or by stable transfection with short hairpin RNA(shRNA) targeting activinA] conditions. Conditioned medium from an OSCC cell line with shRNA‑mediated depletion of activin A was also tested. The profile of pro‑ and anti‑angiogenic factors regulated by activin A was assessed with a human angiogenesis quantitative PCR(qPCR) array. Vascular endothelial growth factor A(VEGFA) and its major isoforms were evaluated by reverse transcription‑qPCR and ELISA. Activin A expression in blood vessels demonstrated an independent prognostic value in the multivariate analysis with a hazard ratio of 2.47 [95%confidence interval(CI), 1.30‑4.71; P=0.006) for disease‑specific survival and 2.09 (95%CI, 1.07‑4.08l: P=0.03) for disease‑free survival. Activin A significantly increased tubular formation of HUVECs concomitantly with an increase in proliferation. This effect was validated by reduced proliferation and tubular formation of HUVECs following inhibition of activin A by follistatin or shRNA, as well as by treatment of HUVECs with conditioned medium from activin A‑depleted OSCC cells. Activin A‑knockdown increased the migration of HUVECs. In addition, activin A stimulated the phosphorylation of SMAD2/3 and the expression and production of total VEGFA, significantly enhancing the expression of its pro‑angiogenic isoform121. The present findings suggest that activin A is a predictor of the prognosis of patients with OSCC, and provide evidence that activin A, in an autocrine and paracrine manner, may contribute to OSCC angiogenesis through differential expression of the isoform 121 of VEGFA.

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

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

MiR-378a-5p inhibits angiogenesis of oral squamous cell carcinoma by targeting KLK4.

Oral squamous cell carcinoma (OSCC) is still a leading cause of cancer death owing to distant metastasis, which is largely facilitated by tumor angiogenesis. MicroRNA (miR)-378a-5p and Kallikrein-related peptidase 4 (KLK4) participate in tumorigenesis and tumor metastasis according to previous studies, yet the exact role they play in tumor angiogenesis remains poorly understood. The aim of the present study is to investigate the effect of miR-378a-5p and KLK4 on angiogenesis of OSCC. MTT assay showed that the expression level of miR-378a-5p was negatively correlated with the proliferation of OSCC cells. ELISA and Western blot assay showed that down-regulation of miR-378a-5p promotes VEGF expression. Tube formation and in vivo chicken chorioallantoic membrane (CAM) assay showed that inhibition of miR-378a-5p reduced tube formation of human umbilical vein endothelial cells (HUVECs) and newly formed microvessel. On the contrary, over-expression of KLK4 enhanced angiogenesis of OSCC cells with increased VEGF expression, tube formation activity of HUVECs and newly formed microvessel. Moreover, the dual-luciferase assay validated that KLK4 was a target gene of miR-378a-5p. MiR-378a-5p silencing induced tube formation was suppressed by the downregulation of KLK4. Besides, the activation of Wnt/β-catenin signaling pathway in miR-378a-5p antagomir transfected cells was also blocked by the KLK4 shRNA. To sum up, our study suggests that miR-378a-5p suppressed angiogenesis of OSCC at least partly by the regulation of KLK4.

Young and elderly oral squamous cell carcinoma patients present similar angiogenic profile and predominance of M2 macrophages: Comparative immunohistochemical study.

M2 macrophages are often detected in oral squamous cell carcinoma (OSCC), which, influenced by hypoxic conditions, appear to have high angiogenesis-inducing capacity. However, the effects of immunosenescence on tumor-associated macrophages (TAMs) and angiogenesis in OSCC are unknown. Fifty-seven OSCCs were divided into 3 groups (I: <40 years [n = 17]; II: 40-65 years [n = 20]; III: >65 years [n = 20]). Immunohistochemistry for CD68 and CD163 (TAMs), and CD34 and D2-40 for microvessel density (MVD), microvessel area (MVA), and total vascular area (TVA) were performed. All groups showed similar clinicopathological and immunohistochemical findings. Similar CD68 and CD163 expression, confirmed a M2 phenotype. MVD, MVA, and TVA were similar, however, with significant predominance of blood vessels. No significant correlation between macrophage and angiogenic markers was observed. A similar TAM and angiogenesis profile suggests the participation of other mechanisms, instead immunosenescence, in young and elderly OSCC patients.

Role of PFKFB3 and CD163 in Oral Squamous Cell Carcinoma Angiogenesis.

6-phosphofructo-2-kinase/fructose-2, 6-biphosphatase 3 (PFKFB3), an enzyme producing fructose 2, 6-bisphosphate (F-2, 6-BP), serves as a switch to activate phosphofructokinase-1, and is a critical enzyme for endothelial glycolysis, mediating circadian control of carcinogenesis. Also, tumor-associated macrophages (TAMs) play an important role in the progression and prognosis of numerous cancers. However, the role and clinical significance of PFKFB3 and TAMs in oral squamous cell carcinoma (OSCC) have not been elucidated. The present study was designed to investigate the correlation between PFKFB3 expression, CD163+ TAMs infiltration and tumor angiogenesis in OSCC by tissue microarray. Tissue microarrays containing 117 OSCC specimens and 56 matched paracarcinoma tissues were studied by immunohistochemistry. The expression levels of PFKFB3, CD163 and CD31 were significantly increased in OSCC specimens as compared with normal oral mucosa (P<0.05), and PFKFB was signifcantly correlated with tumor differentiation and tumor size (P<0.05), and CD163 was significantly correlated with areca nut chewing habit among OSCC tissues (P<0.05). Furthermore, Pearson's correlation analysis revealed that PFKFB3 was signifcantly correlated with both CD163 and CD31 (P<0.05), meanwhile CD163 was signifcantly correlated with CD31 (P<0.001), suggesting PFKFB3 may promote angiogenesis in tumor progression and metastases by regulating CD163+ TAMs infiltration in OSCC.

Overexpression of ADAM10 in oral squamous cell carcinoma with metastases

ADAMs (a disintegrin and metalloproteinase) are important mediators of cell signalling events, which play a role in the pathogenesis and progression of cancers. Immunohistochemical method was used to examine the immunoexpression of ADAM10 and microvessel density in 80 cases of oral squamous cell carcinoma (OSCC): without metastases - OSCC M(-) (n = 38), and with metastases - OSCC M(+) (n = 42), in 24 cases of oral leukoplakia (OLK), (15 cases with low-grade dysplasia - OLK-LG, and 9 cases with high-grade dysplasia - OLK-HG), and 19 controls. The immunoexpression of ADAM10 and the mean number of vessels were significantly increased in both groups of OSCC in comparison to both groups of OLK and controls. Moreover, the immunoexpression of ADAM10 and microvessel density were significantly increased in the OSCC M(+) group in comparison to the OSCC M(-) group. No statistically significant differences were found between immunoexpression of ADAM10 and microvessels density in the OLK-LG, OLK-HG, and control cases. In conclusion, the present study revealed overexpression of ADAM10 in OSCCs, especially in OSCC with metastasis. These findings suggest that ADAM10 could potentially contribute to metastases of oral cancer. Although, our findings suggest that ADAM10 may be involved in angiogenesis of OSCC, further studies are required to determine the role of ADAM10 in this process.

RNAi-mediated downregulation of oral cancer overexpressed 1 (ORAOV1) inhibits vascular endothelial cell proliferation, migration, invasion, and tube formation.

Oral squamous cell carcinoma (OSCC) is one of the top ten tumors threatening human health. Oral cancer overexpressed 1 (ORAOV1) identified within chromosomal region 11q13, one of the most frequently amplified regions in OSCC, has been suggested as a novel candidate oncogene in OSCC, regulating cell cycle, apoptosis, and angiogenesis. In this study, we investigated the role of ORAOV1 in OSCC-induced angiogenesis in vitro. EA.hy926 human endothelial cells were co-cultured with OSCC cells (HSC-3 and SCC-25) transfected with ORAOV1-specific shRNA to downregulate ORAOV1 expression, and analyzed for proliferation, migration, invasion, and tube formation by specific assays. EA.hy926 endothelial cells co-cultured with ORAOV1-deficient OSCC cells exhibited significantly lower proliferation, migration, and invasion, as well as the activity in tube formation compared to that in the control cells. Our results show, for the first time, that ORAOV1 expressed by OSCC cells promotes tube formation by endothelial cells, indicating its involvement in OSCC angiogenesis. Considering the importance of neovascularization in tumor development and metastasis, these findings suggest that targeting ORAOV1 may be a potential therapeutic strategy against OSCC.

WISP-1 a novel angiogenic regulator of the CCN family promotes oral squamous cell carcinoma angiogenesis through VEGF-A expression.

Oral squamous cell carcinoma (OSCC), which accounts for nearly 90% of head and neck cancers, is characterized by poor prognosis and a low survival rate. VEGF-A is the most established angiogenic factor involved in the angiogenic-regulated tumor progression. WISP-1/CCN4 is an extracellular matrix-related protein that belongs to the Cyr61, CTGF, Nov (CCN) family and regulates many biological functions, such as angiogenesis. Previous studies indicated the role of WISP-1 in tumor progression. However, the angiogenic property of WISP-1 in the cancer microenvironment has never been discussed. Here, we provide novel insights regarding the role of WISP-1 in the angiogenesis through promoting VEGF-A expression. In this study, the correlation of WISP-1 and VEGF-A was confirmed by IHC staining of specimens from patients with OSCC. In vitro results indicated that WISP-1 induced VEGF-A expression via the integrin αvβ3/FAK/c-Src pathway, which transactivates the EGFR/ERK/HIF1-α signaling pathway in OSCC. This pathway in turn induces the recruitment of endothelial progenitor cells and triggers the neovascularization in the tumor microenvironment. Our in vivo data revealed that tumor-secreted WISP-1 promoted the angiogenesis through VRGF expression and increased angiogenesis-related tumor growth. Our study offers new information that highlights WISP-1 as a potential novel therapeutic target for OSCC.

Better grade of tumor differentiation of oral squamous cell carcinoma arising in background of oral submucous fibrosis

Oral submucous fibrosis (OSMF) is a potentially malignant disorder of the oral cavity. Most of the people affected by OSMF are betel quid chewers. It is characterized by epithelial atrophy and progressive accumulation of collagen fibers in lamina propria and submucosa of the oral mucosa. 7.6% of OSMF cases undergo oral squamous cell carcinoma (OSCC) transformation of which majority display low grade of tumor differentiation. In the present paper, a hypothesis has been proposed to correlate atrophy, turnover rate and surface keratization in OSMF with degree of tumor differentiation in OSCC. A novel hypothesis for epithelial atrophy in OSMF has also been emphasized.High proliferative activity and basal cell hyperplasia in conjunction with rapid exfoliation of superficial cells and epithelial atrophy suggest that epithelial turnover rate is very high in OSMF. Presence of surface keratinized layer in this situation suggests faster maturation or differentiation of epithelium in OSMF. Thus, the epithelial cells are genetically programmed for high turnover rate and faster differentiation or maturation to form keratin. During malignant transformation of OSMF, the transformed epithelial cells may retain the genetic memory of faster differentiation and maturation resulting in better grade of tumor differentiation. The well differentiated OSCC has good prognosis, better survival rate and less chances of recurrence of regional and distant metastasis. Studies are needed to explore the biomarkers or molecular markers associated with carcinogenesis like genetic instability, oncogenes, tumor suppressor genes and angiogenesis in OSCC associated with OSMF. If investigated in the suggested direction, it might provide some important clues about the pathogenesis of OSCC arising in background of OSMF and for the future development of treatment strategies.

Immunohistochemical analysis of mast cell infiltrates and microvessel density in oral squamous cell carcinoma

The aim of the study was to evaluate mast cell concentration and microvessel density in perilesional and intralesional regions of oral squamous cell carcinoma (OSCC) and furthermore to assess the possible relationship between the above-mentioned parameters. Paraffin-embedded specimens from 47 cases of OSCC and 12 cases of normal mucosa were investigated immunohistochemically with anti-CD-31 antibody to stain microvessels and anti-tryptase antibody to visualize mast cells. The degree of vascularization and mast cell infiltration was measured with an image analysis system. The study revealed considerably increased microvessel density and mast cell abundance in intralesional and perilesional regions of OSCCs in comparison to normal mucosa. There was a significant positive correlation between microvessel density and mast cell concentration in both localizations of OSCCs (p < 0.02, p < 0.001, respectively), whereas a comparable correlation was not observed in normal mucosa. The obtained results suggest that mast cells play an important role in the regulation of angiogenesis in OSCC, although there are aspects of their activity of potential diagnostic and therapeutic significance which require further research.

Comparative immunohistochemical analysis of angiogenesis and mast cell density in oral normal mucosa and squamous cell carcinoma

Background:Squamous cell carcinoma (SCC) is the most common malignancy in oral cavity. Angiogenesis is essential for the development and progression of SCC. Recently, some studies have reported that mast cells may play a role in tumor progression via promoting angiognesis. Since the results of various studies on the role of mast cells in tumor progression is not uniform, the aim of this study was to define the possible role of mast cells in the process of angiogenesis by determining the microvessel density (MVD) and mast cell density (MCD) and the association between them in oral normal mucsoa and oral SCC.Materials and Methods:In this retrospective analytical study, paraffinized specimens from 22 cases of normal mucosa and 20 cases of well-differentiated oral SCC were selected. Microvessels were stained by using immunohistochemical technique with anti-CD34 antibody and mast cells with toluidine blue and then were counted at 400× magnification in hot-spot areas under a light microscope. The results were analyzed by using t- test and Pearson's exams. P values less than 0.05 was considered to be significant.Results:A significant correlation was noted between MVD and MCD in normal oral mucosa (P<0.001), but in spite of a higher density of mast cells and microvessels observed in oral SCC compared to normal mucosa, there was no significant correlation between them (P=0.731).Conclusion:These findings showed that factors other than mast cells may play a role in the upregulation of tumor angiogenesis in oral SCC.

Vesicular stomatitis virus matrix protein (VSVMP) inhibits the cell growth and tumor angiogenesis in oral squamous cell carcinoma

The purpose of this study was to investigate the anticancer property of vesicular stomatitis virus matrix protein (VSVMP) in oral squamous cell carcinoma (OSCC) via in vitro and in vivo approaches. In this study, we found that OSCC cells treated with VSVMP showed retarded cell growth in vitro. The percentage of apoptotic cells in VSVMP group was much higher than that of the control groups. Moreover, our in vivo experiments showed that the growth of tumor xenografts was significantly suppressed by VSVMP treatment without any obvious side effects. Further studies revealed that the suppression of tumor growth may be caused by the synergistic effect of VSVMP related cell apoptosis enhancing and tumor angiogenesis suppression, and the latter is most likely correlated with the suppression of VEGF pathway. This study indicated that VSVMP treatment can effectively inhibited the cell growth and tumor angiogenesis in OSCC without obvious adverse effects. Therefore, VSVMP might be a potential and efficient strategy for OSCC treatment.

Role of angiogenesis in oral squamous cell carcinoma development and metastasis: an immunohistochemical study

Although a few studies have shown that vascularity is increased from normal mucosa to dysplasia to carcinoma suggesting that disease progression in the oral mucosa is accompanied by angiogenesis. The role in lymph node metastasis in oral squamous cell carcinoma (OSCC) is equivocal. Role of angiogenesis in OSCC development and metastasis is evaluated in this study. This retrospective study of 50 samples consisted of 9 normal buccal mucosa, 22 leukoplakias, and 19 OSCC. Polyclonal antibodies to von-Willebrand factor were used to highlight the microvessels. Images were captured and morphometric image analysis was done for microvessel density (MVD), area, and perimeter. Highest, as well as mean values of these three parameters were compared. MVD and perimeter, but not area, are significantly different between normal mucosa and OSCC, and leukoplakia and OSCC. There were no differences between normal mucosa and leukoplakia. MVD, area, and perimeter were not significantly different between the OSCC with and without lymph node metastasis. The highest and mean values of MVD are significantly correlated. In the development of OSCC, angiogenic phenotypic change occurs in carcinomas rather than in the pre-cancerous stage, and quantification of angiogenesis in OSCC does not predict the risk of lymph node metastasis.