Cyclooxygenase-2 promotes tumor lymphangiogenesis and lymph node metastasis in oral squamous cell carcinoma

Tumor microenvironment dynamics in oral cancer: unveiling the role of inflammatory cytokines in a syngeneic mouse model

The process of cervical lymph node metastasis is dependent on the phenotype of the tumor cells and their interaction with the host microenvironment and immune system; conventional research methods that focus exclusively on tumor cells are limited in their ability to elucidate the metastatic mechanism. In cancer tissues, a specialized environment called the tumor microenvironment (TME) is established around tumor cells, and inflammation in the TME has been reported to be closely associated with the development and progression of many types of cancer and with the response to anticancer therapy. In this study, to elucidate the mechanism of metastasis establishment, including the TME, in the cervical lymph node metastasis of oral cancer, we established a mouse-derived oral squamous cell carcinoma cervical lymph node highly metastatic cell line and generated a syngeneic orthotopic transplantation mouse model. In the established highly metastatic cells, epithelial-mesenchymal transition (EMT) induction was enhanced compared to that in parental cells. In the syngeneic mouse model, lymph node metastasis was observed more frequently in tumors of highly metastatic cells than in parental cells, and Cyclooxygenase-2 (COX-2) expression and lymphatic vessels in primary tumor tissues were increased, suggesting that this model is highly useful. Moreover, in the established highly metastatic cells, EMT induction was enhanced compared to that in the parent cell line, and CCL5 and IL-6 secreted during inflammation further enhanced EMT induction in cancer cells. This suggests the possibility of a synergistic effect between EMT induction and inflammation. This model, which allows for the use of two types of cells with different metastatic and tumor growth potentials, is very useful for oral cancer research involving the interaction between cancer cells and the TME in tumor tissues and for further searching for new therapeutic agents.

Naturally Isolated Sesquiterpene Lactone and Hydroxyanthraquinone Induce Apoptosis in Oral Squamous Cell Carcinoma Cell Line

Oral squamous cell carcinoma (OSCC) is one of the most prevalent cancers worldwide, especially in Asian countries. The emergence of its drug resistance and its side effects demands alternatives, to improve prognosis. Since the majority of cancer drugs are derived from natural sources, it provides a window to look for more biocompatible alternatives. In this study, two natural compounds, costunolide (CE) and aloe emodin (AE), were isolated from the stem of Lycium shawii. The compounds were examined for their anticancer and apoptotic potentials against OSCC (CAL 27) cells, using an in vitro analysis, such as a MTT assay, scratch assay, gene, and protein expressions. Both compounds, CE and AE, were found to be cytotoxic against the cancer cells with an IC₅₀ value of 32 and 38 µM, respectively. Moreover, the compounds were found to be non-toxic against normal NIH-3T3 cells and comparable with the standard drug i.e., 5-fluorouracil (IC₅₀ = 97.76 µM). These compounds were active against normal cells at higher concentrations. Nuclear staining displayed the presence of apoptosis-associated morphological changes, i.e., karyopyknosis and karyorrhexis in the treated cancer cells. Flow cytometry results further confirmed that these compounds induce apoptosis rather than necrosis, as the majority of the cells were found in the late apoptotic phase. Gene and protein expression analyses showed an increased expression of apoptotic genes, i.e., BAK, caspase 3, 6, and 9. Moreover, the compounds significantly downregulated the expression of the anti-apoptotic (BCL-2 L1), metastatic (MMP-2), and pro-inflammatory (COX-2) genes. Both compounds have shown promising anticancer, apoptotic, and anti-migratory activities against the OSCC cell line (i.e., CAL-27). However, further in vivo studies are required to explore these compounds as anticancer agents.

Lymphatic vessels in cancer

The lymphatic system, composed of initial and collecting lymphatic vessels as well as lymph nodes that are present in almost every tissue of the human body, acts as an essential transport system for fluids, biomolecules and cells between peripheral tissues and the central circulation. Consequently, it is required for normal body physiology but is also involved in the pathogenesis of various diseases, most notably cancer. The important role of tumor-associated lymphatic vessels and lymphangiogenesis in the formation of lymph node metastasis has been elucidated during the last two decades, whereas the underlying mechanisms and the relation between lymphatic and peripheral organ dissemination of cancer cells are incompletely understood. Lymphatic vessels are also important for tumor-host communication, relaying molecular information from a primary or metastatic tumor to regional lymph nodes and the circulatory system. Beyond antigen transport, lymphatic endothelial cells, particularly those residing in lymph node sinuses, have recently been recognized as direct regulators of tumor immunity and immunotherapy responsiveness, presenting tumor antigens and expressing several immune-modulatory signals including PD-L1. In this review, we summarize recent discoveries in this rapidly evolving field and highlight strategies and challenges of therapeutic targeting of lymphatic vessels or specific lymphatic functions in cancer patients.

Overview on Molecular Biomarkers for Laryngeal Cancer: Looking for New Answers to an Old Problem

Laryngeal squamous cell cancer (LSCC) accounts for almost 25-30% of all head and neck squamous cell cancers and is clustered according to the affected districts, as this determines distinct tendency to recur and metastasize. A major role for numerous genetic alterations in driving the onset and progression of this neoplasm is emerging. However, major efforts are still required for the identification of molecular markers useful for both early diagnosis and prognostic definition of LSCC that is still characterized by significant morbidity and mortality. Non-coding RNAs appear the most promising as they circulate in all the biological fluids allowing liquid biopsy determination, as well as due to their quick and characteristic modulation useful for non-invasive detection and monitoring of cancer. Other critical aspects are related to recent progress in circulating tumor cells and DNA detection, in metastatic status and chemo-refractoriness prediction, and in the functional interaction of LSCC with chronic inflammation and innate immunity. We review all these aspects taking into account the progress of the technologies in the field of next generation sequencing.

Head and Neck Squamous Cell Carcinoma: Risk Factors, Molecular Alterations, Immunology and Peptide Vaccines

Head and neck squamous cell carcinoma (HNSCC) arises from the epithelial lining of the oral cavity, hypopharynx, oropharynx, and larynx. There are several potential risk factors that cause the generation of HNSCC, including cigarette smoking, alcohol consumption, betel quid chewing, inadequate nutrition, poor oral hygiene, HPV and Epstein–Barr virus, and Candida albicans infections. HNSCC has causative links to both environmental factors and genetic mutations, with the latter playing a more critical role in cancer progression. These molecular changes to epithelial cells include the inactivation of cancer suppressor genes and proto-oncogenes overexpression, resulting in tumour cell proliferation and distant metastasis. HNSCC patients have impaired dendritic cell (DC) and natural killer (NK) cell functions, increased production of higher immune-suppressive molecules, loss of regulatory T cells and co-stimulatory molecules and major histocompatibility complex (MHC) class Ι molecules, lower number of lymphocyte subsets, and a poor response to antigen-presenting cells. At present, the standard treatment modalities for HNSCC patients include surgery, chemotherapy and radiotherapy, and combinatorial therapy. Despite advances in the development of novel treatment modalities over the last few decades, survival rates of HNSCC patients have not increased. To establish effective immunotherapies, a greater understanding of interactions between the immune system and HNSCC is required, and there is a particular need to develop novel therapeutic options. A therapeutic cancer vaccine has been proposed as a promising method to improve outcome by inducing a powerful adaptive immune response that leads to cancer cell elimination. Compared with other vaccines, peptide cancer vaccines are more robust and specific. In the past few years, there have been remarkable achievements in peptide-based vaccines for HNSCC patients. Here, we summarize the latest molecular alterations in HNSCC, explore the immune response to HNSCC, and discuss the latest developments in peptide-based cancer vaccine strategies. This review highlights areas for valuable future research focusing on peptide-based cancer vaccines.

Oncolytic herpes virus G47Δ injected into tongue cancer swiftly traffics in lymphatics and suppresses metastasis

The prognosis of oral squamous cell carcinoma (OSCC) largely depends on the control of lymph node metastases. We evaluate the therapeutic efficacy of G47Δ, a third-generation oncolytic herpes simplex virus type 1 (HSV-1), in mouse tongue cancer models. Intratumoral injection with G47Δ prolonged the survival in all orthotopic models investigated. In both athymic and immunocompetent models, G47Δ injected into the tongue cancer swiftly traffics to the draining cervical lymph nodes and suppresses lymph node metastases. In the immunocompetent KLN205-MUC1 model, in which the metastatic cascade that tongue cancer patients commonly experience is reproduced, intratumoral G47Δ injection even immediately prior to a tumor resection prolonged survival. Cervical lymph nodes 18 h after G47Δ treatment showed the presence of G47Δ infection and an increase in CD69-positive cells, indicating an immediate activation of T cells. Furthermore, G47Δ injected directly into enlarged metastatic lymph nodes significantly prolonged the survival at an advanced stage. Whereas intratumorally injected oncolytic HSV-1 does not readily circulate in the blood stream, G47Δ is shown to traffic in the lymphatics swiftly. The use of G47Δ can lead to entirely new treatment strategies for tongue cancer and other OSCC at all clinical stages.

Transcriptomic Profiling Predicts Multiple Pathways and Molecules Associated With the Metastatic Phenotype of Oral Cancer Cells

BACKGROUND/AIM

Metastasis to cervical lymph nodes of oral squamous cell carcinoma (OSCC) leads to a poor prognosis. The present study aimed at investigating the pathways and molecules associated with OSCC metastasis.

MATERIALS AND METHODS

The transcriptome between HSC-3 cells and their highly metastatic subline, HSC-3-M3 cells, was examined using gene expression microarray. Gene enrichment analyses and Ingenuity Pathway Analysis were performed. Kaplan-Meier plot analysis using a publicly available dataset was conducted to assess whether candidate molecules are prognosticators.

RESULTS

A total of 1,018 genes were differentially expressed, and the inflammatory pathway and NF-kB were predicted to be activated in HSC-3-M3 cells. CSF2 was suggested to be an indicator of poor prognosis in head and neck cancers.

CONCLUSION

Inflammation and NF-kB may be involved in the metastasis of OSCC, and CSF2 is a promising diagnostic and therapeutic molecule. Moreover, HSC-3-M3 cells are a useful cell line model for studying OSCC progression.

Expression and clinical implication of cyclooxygenase-2 and E-cadherin in oral squamous cell carcinomas

Epithelial-Mesenchymal Transition (EMT) and angiogenesis are crucial events for development of aggressive and often fatal Oral Squamous Cell Carcinomas (OSCCs). Both promote cancer progression and metastasis development, but while the former induces the loss of E-cadherin expression and, hence cadherin switching; the latter produces hematic blood vessel neo-formation and contribute to OSCC cell growth, tumor mass development, and dissemination. Cyclooxygenase-2 (COX-2) has an important role, not only in angiogenic mechanisms, but also in favoring cancer invasion. Indeed it decreases the expression of E-cadherin and leads to phenotypic changes in epithelial cells (EMT) enhancing their carcinogenic potential. Our aim is to evaluate the interplay between E-cadherin cytoplasmic delocalization, COX-2 up-regulation and COX-2 induced neo-angiogenesis in 120 cases of OSCC. We have analyzed the distribution and the number of neo-formed endothelial buds surrounding infiltrating cells that express COX-2, as well as the neo-formed vessels in chronic inflammatory infiltrate, which surround the tumor. A double immunostaining method was employed in order to verify co-localization of endothelial cell marker (CD34) and COX-2. IHC has also been used to assess E-cadherin expression. Our data demonstrate that the OSCC cells, which lose membranous E-cadherin staining, acquiring a cytoplasmic delocalization, overexpress COX-2. Moreover, we find a new CD34+ vessel formation (sprouting angiogenesis). Only basaloid type of OSCC showes low level of COX-2 expression together with very low level of neo-angiogenesis and consequent tumor necrosis. The well-known anti-metastatic effect of certain COX-2 inhibitors suggests that these molecules might have clinical utility in the management of advanced cancers.

Isoform-Specific Role of Akt in Oral Squamous Cell Carcinoma

Protein kinase B (Akt) plays a very significant role in various cancers including oral cancer. However, it has three isoforms (Akt1, Akt2, and Akt3) and they perform distinct functions and even play contrasting roles in different cancers. Therefore, it becomes essential to evaluate the isoform-specific role of Akt in oral cancer. In the present study, an attempt has been made to elucidate the isoform-specific role of Akt in oral cancer. The immunohistochemical analysis of oral cancer tissues showed an overexpression of Akt1 and 2 isoforms but not Akt3. Moreover, the dataset of "The Cancer Genome Atlas" for head and neck cancer has suggested the genetic alterations of Akt1 and 2 tend to be associated with the utmost poor clinical outcome in oral cancer. Further, treatment of oral cancer cells with tobacco and its components such as benzo(a)pyrene and nicotine caused increased mRNA levels of Akt1 and 2 isoforms and also enhanced the aggressiveness of oral cancer cells in terms of proliferation, and clonogenic and migration potential. Finally, silencing of Akt1 and 2 isoforms caused decreased cell survival and induced cell cycle arrest at the G2/M phase. Akt1/2 silencing also reduced tobacco-induced aggressiveness by decreasing the clonogenic and migration potential of oral cancer cells. Moreover, silencing of Akt1 and 2 isoforms was found to decrease the expression of proteins regulating cancer cell survival and proliferation such as cyclooxygenase-2, B-cell lymphoma 2 (Bcl-2), cyclin D1, and survivin. Thus, the important role of Akt1 and 2 isoforms have been elucidated in oral cancer with in-depth mechanistic analysis.

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

OBJECTIVES

In oral squamous cell carcinoma (OSCC), cyclooxygenases (COX-1 and COX-2) contribute to inflammation, and cluster of differentiation factor 147 (CD147) contributes to invasiveness, but their relationship has not been previously examined within a cohort of patients with OSCC or OSCC cell lines.

STUDY DESIGN

COX-2 and CD147 expression was determined by using immunohistochemistry on 39 surgical biopsy specimens of OSCC. Expression in tumor cells, stroma, and adjacent oral epithelium was characterized by using a visual grading system. COX-1, COX-2, and CD147 expression was determined in vitro by using OSCC cell lines (SCC25, BHY, and HN) and reverse transcriptase-quantitative polymerase chain reaction. Secretion of prostagladin E₂ (PGE₂) from OSCC cell lines was determined by using PGE₂ enzyme-linked immunosorbent assay.

RESULTS

Biopsy specimens showed higher COX-2 expression in tumor cells compared with stroma and adjacent epithelium (P < .05). There was no difference in CD147 expression among the tumor cells, stroma, and adjacent epithelium. In OSCC cell lines, there was a trend for COX-2 and CD147 gene expression to be coordinated. Interestingly, PGE₂ secretion was more closely related to COX-1 expression than to COX-2 expression.

CONCLUSIONS

COX-1, COX-2, and CD147 appear to be independently regulated in OSCC, potentially representing 2 therapeutic targets for future investigation. COX-1 expression in OSCC deserves further study because it may be an important determinant of PGE₂ secretion from OSCC cells.

Lymphatic changes in cancer and drug delivery to the lymphatics in solid tumors

Although many solid tumors use the lymphatic system to metastasize, there are few treatment options that directly target cancer present in the lymphatic system, and those that do are highly invasive, uncomfortable, and/or have limitations. In this review we provide a brief overview of lymphatic function and anatomy, discusses changes that befall the lymphatics in cancer and the mechanisms by which these changes occur, and highlight limitations of lymphatic drug delivery. We then go on to summarize relevant techniques and new research for targeting cancer populations in the lymphatics and enhancing drug delivery intralymphatically, including intralymphatic injections, isolated limb perfusion, passive nano drug delivery systems, and actively targeted nanomedicine.

Three-dimensional cultured tissue constructs that imitate human living tissue organization for analysis of tumor cell invasion

Preventing cancer metastasis requires a thorough understanding of cancer cell invasion. These phenomena occur in human 3-D living tissues. To this end, we developed a human cell-based three-dimensional (3-D) cultured tissue constructs that imitate in vivo human tissue organization. We investigated whether our 3-D cell culture system can be used to analyze the invasion of human oral squamous cell carcinoma (OSCC) cells. The 3-D tissue structure consisted of five layers of normal human dermal fibroblasts along with human dermal lymphatic endothelial cell tubes and was generated by the cell accumulation technique and layer-by-layer assembly using fibronectin and gelatin. OSCC cells with different lymph metastatic capacity were inoculated on the 3-D tissues and their invasion through the 3-D tissue structure was observed. Conventional methods of analyzing cell migration and invasion, that is, 2-D culture-based transwell and Matrigel assays were also used for comparison. The results using the 3-D cultured tissue constructs were comparable to those obtained using conventional assays; moreover, use of the 3-D system enabled visualization of differential invasion capacities of cancer cells. These results indicate that our 3-D cultured tissue constructs can be a useful tool for analysis of cancer cell invasion in a setting that reflects the in vivo tissue organization. © 2018 The Authors. Journal of Biomedical Materials Research Part A published by Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 292-300, 2019.

Role of COX-2/PGE2 Mediated Inflammation in Oral Squamous Cell Carcinoma

A significant amount of research indicates that the cyclooxygenase/prostaglandin E2 (PGE2) pathway of inflammation contributes to the development and progression of a variety of cancers, including squamous cell carcinoma of the oral cavity and oropharynx (OSCC). Although there have been promising results from studies examining the utility of anti-inflammatory drugs in the treatment of OSCC, this strategy has been met with only variable success and these drugs are also associated with toxicities that make them inappropriate for some OSCC patients. Improved inflammation-targeting therapies require continued study of the mechanisms linking inflammation and progression of OSCC. In this review, a synopsis of OSCC biology will be provided, and recent insights into inflammation related mechanisms of OSCC pathobiology will be discussed. The roles of prostaglandin E2 and cluster of differentiation factor 147 (CD147) will be presented, and evidence for their interactions in OSCC will be explored. Through continued investigation into the protumourigenic pathways of OSCC, more treatment modalities targeting inflammation-related pathways can be designed with the hope of slowing tumour progression and improving patient prognosis in patients with this aggressive form of cancer.

Clinicopathological and prognostic significance of cyclooxygenase-2 expression in head and neck cancer: A meta-analysis

Several studies have assessed the clinicopathological and prognostic value of cyclooxygenase-2 (COX-2) expression in patients with head and neck cancer (HNC), but their results remain controversial. To address this issue, a meta-analysis was carried out. A total of 29 studies involving 2430 patients were subjected to final analysis. Our results indicated that COX-2 expression was not statistically associated with advanced tumor stage (OR, 1.23; 95% CI, 0.98–1.55) but correlated with high risk of lymph node metastasis (OR, 1.28; 95% CI, 1.03–1.60) and advanced TNM stage (OR, 1.33; 95% CI, 1.06–1.66). Moreover, COX-2 expression had significant effect on poor OS (HR, 1.93; 95% CI, 1.29–2.90), RFS (HR, 2.02; 95% CI, 1.00–4.08) and DFS (HR, 5.14; 95% CI, 2.84–9.31). The results of subgroup analyses revealed that COX-2 expression was related with high possibility of lymph node metastasis in oral cancer (OR, 1.49; 95% CI, 1.01–2.20) and advanced TNM stage in oral cancer (OR, 1.58; 95% CI, 1.05–2.37) and no site-specific HNC (OR, 1.64; 95% CI, 1.02–2.62). However, subgroup analyses only showed a tendency without statistically significant association between COX-2 expression and survival. Significant heterogeneity was not found when analyzing clinicopathological data, but it appeared when considering survival data. No publication bias was detected in this study. This meta-analysis suggested that COX-2 expression could act as a prognostic factor for patients with HNC.

Stromal versus tumoral inflammation differentially contribute to metastasis and poor survival in laryngeal squamous cell carcinoma

In solid tumors the biology and clinical course are strongly influenced by the interaction of tumor cells and infiltrating stromal host cells. The aim of this study was to assess the relative importance of stromal vs. tumoral inflammation for metastasis and survival in patients with laryngeal squamous cell carcinoma (LSCC).

In 110 patients with tissues from histologically proven LSCC the expression of CD45, CD11b, CD3, MMP-9 and COX-2 was semiquantitatively analyzed in stromal regions and tumor nests.

CD45, CD11b, CD3 and MMP-9 positive cells were more abundant in stroma whereas COX-2 was predominantly expressed in epithelial tumor nests. High expression of stromal CD45 and CD11b on immune cells in tumor regions correlated with COX-2 expression on tumor cells. High levels of CD45 in stroma as well as CD11b and COX-2 in tumor nests were associated with increased metastasis. In contrast, high frequencies of CD3 cells in the tumor core area were associated with reduced metastasis. Overall survival was reduced in patients with high stromal CD45, high tumoral CD11b and high tumoral COX-2 expression.

This is the first study which separately analyzes peritumoral stroma and tumor core area in laryngeal squamous cell carcinoma in terms of CD45, CD11b, CD3, MMP-9 and COX-2 expression. Our results indicate that stroma and tumor islands need to be considered as two separate compartments in the inflammatory tumor microenvironment. Inflammatory stromal leukocytes, abundant myeloid cells in tumor regions and high expression of COX-2 on tumor cells are linked to metastatic disease and poor overall survival.

Insulin-like growth factor-independent insulin-like growth factor binding protein 3 promotes cell migration and lymph node metastasis of oral squamous cell carcinoma cells by requirement of integrin β1

Frequent metastasis to the cervical lymph nodes leads to poor survival of patients with oral squamous cell carcinoma (OSCC). To understand the underlying mechanisms of lymph node metastasis, two sublines were successfully isolated from cervical lymph nodes of nude mice through in vivo selection, and identified as originating from poorly metastatic parental cells. These two sublines specifically metastasized to cervical lymph nodes in 83% of mice, whereas OEC-M1 cells did not metastasize after injection into the oral cavity. After gene expression analysis, we identified insulin-like growth factor binding protein 3 (IGFBP3) as one of the significantly up-regulated genes in the sublines in comparison with their parental cells. Consistently, meta-analysis of the public microarray datasets and IGFBP3 immunohistochemical analysis revealed increased both levels of IGFBP3 mRNA and protein in human OSCC tissues when compared to normal oral or adjacent nontumorous tissues. Interestingly, the up-regulated IGFBP3 mRNA expression was significantly associated with OSCC patients with lymph node metastasis. IGFBP3 knockdown in the sublines impaired and ectopic IGFBP3 expression in the parental cells promoted migration, transendothelial migration and lymph node metastasis of orthotopic transplantation. Additionally, ectopic expression of IGFBP3 with an IGF-binding defect sustained the IGFBP3-enhanced biological functions. Results indicated that IGFBP3 regulates metastasis-related functions of OSCC cells through an IGF-independent mechanism. Furthermore, exogenous IGFBP3 was sufficient to induce cell motility and extracellular signal-regulated kinase (ERK) activation. The silencing of integrin β1 was able to impair exogenous IGFBP3-mediated migration and ERK phosphorylation, suggesting a critical role of integrin β1 in IGFBP3-enchanced functions.

Tumor lymphangiogenesis and new drug development

Traditionally, tumor-associated lymphatic vessels have been regarded as passive by-standers, serving simply as a drainage system for interstitial fluid generated within the tumor. However, with growing evidence that tumors actively induce lymphangiogenesis, and that the number of lymphatic vessels closely correlates with metastasis and clinical outcome in various types of cancer, this picture has changed dramatically in recent years. Tumor-associated lymphatic vessels have now emerged as a valid therapeutic target to control metastatic disease, and the first specific anti-lymphangiogenic drugs have recently entered clinical testing. Furthermore, we are just beginning to understand the whole functional spectrum of tumor-associated lymphatic vessels, which not only concerns transport of fluid and metastatic cells, but also includes the regulation of cancer stemness and specific inhibition of immune responses, opening new venues for therapeutic applications. Therefore, we predict that specific targeting of lymphatic vessels and their function will become an important tool for future cancer treatment.

Downregulation of Microrna-148a in Cancer-Associated Fibroblasts from Oral Cancer Promotes Cancer Cell Migration and Invasion by Targeting Wnt10b

It is well established that crosstalk between cancer-associated fibroblasts (CAFs) and cancer cells plays a critical role in the occurrence and development of oral squamous cell carcinoma (OSCC). The molecular mechanisms underlying such interaction, however, remain far from clear. Accumulating data have indicated that microRNAs involved in tumor microenvironment, particularly in CAFs, contribute to the activation of fibroblasts and metastasis of cancer cells. Here, we showed that miR-148a was downregulated in CAFs compared with normal fibroblasts isolated from clinical OSCC tissue. Investigation of miR-148a function in fibroblasts demonstrated that overexpression of miR-148a in CAFs significantly impaired the migration and invasion of oral carcinoma cells (SCC-25) by directly targeting WNT10B. Taken together, these data suggested that miR-148a might be a novel candidate target for the treatment of OSCC.

Cellular fibronectin 1 promotes VEGF-C expression, lymphangiogenesis and lymph node metastasis associated with human oral squamous cell carcinoma

Lymph node metastasis (LNM) is associated with poor survival in patients with oral squamous cell carcinoma (OSCC). Vascular endothelial growth factor-C (VEGF-C) is thought to be responsible for increased lymphangiogenesis and LNM. Understanding of the mechanism by which VEGF-C expression is regulated in OSCC is thus important to design logic therapeutic interventions. We showed that inoculation of the SAS human OSCC cells expressing the venus GFP (V-SAS cells) into the tongue in nude mice developed LNM. V-SAS cells in LNM were isolated by FACS and re-inoculated into the tongue. This procedure was repeated eight times, establishing V-SAS-LM8 cells. Differential metastasis PCR array between the parental V-SAS and V-SAS-LM8 was performed to identify a molecule responsible for lymphangiogenesis and LNM. Fibronectin 1 (FN1) expression was elevated in V-SAS-LM8 cells compared to V-SAS-cells. V-SAS-LM8 tongue tumor showed increased expression of FN1 and VEGF-C, and promoted lymphangiogenesis and LNM compared with V-SAS tumor. Further, phosphorylation of focal adhesion kinase (FAK), a main downstream signaling molecule of FN1, was up-regulated, and epithelial-mesenchymal transition (EMT) was promoted in V-SAS-LM8 cells. Silencing of FN1 by shRNA in V-SAS-LM8 cells decreased FAK phosphorylation, VEGF-C expression and inhibited lymphangiogenesis and LNM. EMT was also reversed. The FAK phosphorylation inhibitor PF573228 also decreased VEGF-C expression and reversed EMT in V-SAS-LM8 cells. Finally, we detected intense FN1 expression in some clinical specimens obtained from OSCC patients with LNM. These results demonstrate that elevated expression of cellular FN1 and following activation of FAK lead to increased VEGF-C expression, lymphangiogenesis and LNM and promoted EMT in SAS human OSCC cells and suggest that FN1-phosphorylated FAK signaling cascade is a potential therapeutic target in the treatment of LNM in OSCC.

Cyclooxygenase-2--An Imperative Prognostic Biomarker in Oral Squamous Cell Carcinoma--An Immunohistochemical Study

Oral squamous cell carcinoma (OSCC) is the most common head and neck squamous cell carcinoma (HNSCC) with metastasis and tumor recurrence resulting in 90 % of cancer associated mortality. COX-2, an inflammatory biomarker, has been shown to play a significant role in tumorigenesis of OSCC. To study the expression of COX-2 in OSCC by immunohistochemistry and investigate its association with the clinicopathological parameters including patient survival. A cross sectional study was carried out in 75 histologically confirmed cases of OSCC. COX-2 expression was evaluated by indirect streptavidin biotin method. The expression was semi-quantitatively assessed using established criteria. The expression profile of COX-2 was correlated with the clinicopathological details like tumor size, regional lymphnode metastasis, distant metastasis, clinical stage, local recurrence of tumor, histological grade, and survival of patient. Chi square and Kaplan Meier statistical tests were applied for assessing this association. COX-2 expression was absent in normal oral mucosa. Over expression of COX-2 was seen in 58 out of 75 specimens of OSCC. Overexpression of COX-2 was significantly associated with the lymphnode involvement, histological grade, local recurrence of tumor and patient survival. COX-2 expression represents an important biomarker of prognostic significance that may be used to identify a subset of patients at high risk and to predict patient survival.

Designing biomarker studies for head and neck cancer

Although there is ample literature reporting on the identification of molecular biomarkers for head and neck squamous cell carcinoma, none is currently recommended for routine clinical use. A major reason for this lack of progress is the difficulty in designing studies in head and neck cancer to clearly establish the clinical utility of biomarkers. Consequently, biomarker studies frequently stall at the initial discovery phase. In this article, we focus on biomarkers for use in clinical management, including selection of therapy. Using several contemporary examples, we identify some of the common deficiencies in study design that hinder success in biomarker development for this disease area, and we suggest some potential solutions. The purpose of this article is to provide guidance that can assist investigators to more efficiently move promising biomarkers in head and neck cancer from discovery to clinical practice

Smoking-induced changes in cancer-related factors in patients with upper tract urothelial cancer

Cigarette smoking is a major risk factor for urothelial cancer (UC) development. However, the associations between smoking and changes in the pathological characteristics and molecular expression of cancer-related molecules in upper tract (UT) UC have not been fully elucidated. We investigated the associations between smoking status and cancer-related factors, including cancer cell proliferation, apoptosis, angiogenesis, lymphangiogenesis and expression of vascular endothelial growth factor-A and -C, matrix metalloproteinase (MMP)-2 and -9, cyclooxygenase (COX)-2 and urokinase-type plasminogen activator, in patients with UTUC. A total of 134 patients who underwent nephroureterectomy were retrospectively investigated. Proliferation index (PI), microvessel density and lymphatic vessel density (LVD) were measured using anti-Ki-67, anti-CD105 and anti-D2-40 antibodies in formalin-fixed specimens. The apoptotic index was evaluated using the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling method. Other cancer-related molecules were investigated by immunohistochemistry in similar specimens. The patients were divided into three groups; non-smoker (n=54, 40.3%), former smoker (n=46, 34.3%) and current smoker (n=34, 25.4%). The PI and the apoptotic index were not found to be correlated with smoking status; however, the mean/standard deviation level of LVD in current smokers (40.9/12.9) was significantly higher (P=0.034) compared to that in patients who had never smoked (34.4/10.6). In addition, smoking status was positively correlated with the presence of intratumoral lymphatic vessels (iLV) (P=0.010) and the expression of COX-2 and MMP-9 (P=0.032). The multivariate analysis demonstrated that current smoking was independently associated with all the abovementioned smoking-related factors. However, former smoking was correlated with LVD and the presence of iLV. In the survival analysis, LVD, the presence of iLV and the expression of COX-2 and MMP-9 were identified as predictive factors for metastasis following surgery. In conclusion, lymphangiogenesis and the expression levels of COX-2 and MMP-9 were found to be associated with the smoking status of UTUC patients. Our results may provide important insights into the pathological changes precipitated by smoking in these patients.

Celecoxib attenuates cachectic events in mice by modulating the expression of vascular endothelial growth factor

Chronic inflammation is one of the main symptoms of cancer cachexia, and cyclooxygenase 2 inhibitors, such as celecoxib, may be beneficial in counteracting the major symptoms of this syndrome. In the current study, celecoxib was orally administered to BALB/c male mice with colon 26 adenocarcinoma. Tumor growth, survival rate, body weight and food intake of the mice with cancer cachexia were recorded during the experiments. The host inflammatory response was assessed by morphological observations and hematoxylin-eosin staining. The serum levels of vascular endothelial growth factor (VEGF), granulocyte-macrophage colony-stimulating factor, interleukin-6 and tumor necrosis factor-α in mice with cancer cachexia were measured by ELISA. Celecoxib administration attenuated the decline in body weight and food intake of mice with cancer cachexia, and improved the survival rate of cachectic mice. Erythrocyte counts and hemoglobin concentration significantly increased in cachectic mice receiving celecoxib compared with control cachectic mice. Notably, celecoxib administration significantly reduced the serum level of VEGF in mice with colon 26 adenocarcinoma, and the cachectic events were also relieved by treatment with a VEGF antibody. The cyclooxygenase 2 inhibitor celecoxib produced positive therapeutic effects in mice with cancer cachexia. This function was regulated at least partly by downregulation of serum levels of VEGF.

Zoledronic acid induces apoptosis and autophagy in cervical cancer cells

Cervical cancer is one of the most common gynecological cancers in association with high mortality and morbidity. The present study was aimed to investigate the in vitro effects of zoledronic acid (ZA) on viability and induction of apoptosis and autophagy as well as inflammatory effects in three human cervical cancer cell lines (HeLa, SiHa, and CaSki). Cell viability was measured by 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay. Induction of apoptosis was determined by quantitation of expression level of B cell lymphoma 2 (Bcl-2) and Bax messenger RNA (mRNA) and identification of the proteolytic cleavage of poly (ADP)-ribose polymerase (PARP) and caspase-3. Autophagic effects were examined by quantitation of mRNA expression of autophagy protein 5 (ATG5) and beclin1 and identifying accumulation of microtubule-associated protein 1 light chain 3 (LC3)-II. Inflammatory effect was determined by measuring expression and production of IL-6 and cyclooxygenase-2 (Cox-2). The results showed ZA significantly inhibited cell viability of cervical cancer cells. ZA-induced cell death displayed features characteristic to both apoptosis and autophagy and was associated with different changes in the levels of Bcl-2 and Bax in the various cervical cancer lines. Expression of metastatic cytokines, IL-6 and Cox-2, was upregulated in the presence of ZA at low concentration. Our data revealed that ZA inhibits cervical cancer cells through the synergistic effect of apoptosis induction and autophagy activation.

Metastatic potential in MDA-MB-231 human breast cancer cells is inhibited by proton beam irradiation via the Akt/nuclear factor-κB signaling pathway

A previous study has revealed that proton beam irradiation affects cell migration in MDA-MB-231 human breast cancer cells. Cyclooxygenase-2 (COX-2) and matrix metalloproteinase‑9 (MMP-9) are highly expressed in various cancers, such as colon, lung and breast cancer, and enhance cell migration and metastasis in vitro and in vivo. In the present study, the effects of proton beam irradiation on COX-2 and MMP-9 expression levels in MDA-MB‑231 human breast cancer cells were investigated, along with the signaling pathway involved in the proton beam irradiation‑mediated antimetastatic effect. The results revealed that 12-O-tetradecanoylphorbol-13‑acetate‑induced increases in COX-2 and MMP-9 expression levels were reversed by proton beam irradiation in a dose-dependent manner. In addition, proton beam irradiation inhibited phosphorylation of protein kinase B (also known as Akt) and nuclear factor-κB (NF-κB), which are activated by phosphoinositide 3-kinase (PI3K) stimulation. MMP-9 and COX-2 expression levels are regulated by PI3K/Akt and/or protein kinase C/mitogen-activated protein kinase signaling pathways that enhance NF-κB and activator protein-1 transcriptional activities. Therefore, the results suggest that proton beam irradiation inhibited the cancer cell growth and metastasis associated with COX-2 and MMP-9 expression in MDA-MB‑231 human breast cancer cells, and that the antimetastatic effect of proton beam irradiation is achieved by the suppression of NF-κB phosphorylation via inhibition of Akt activation.

HIF-1α and CA-IX as predictors of locoregional control for determining the optimal treatment modality for early-stage laryngeal carcinoma

BACKGROUND

The purpose of this study was to examine the predictive value of hypoxia-inducible factor (HIF)-1α, carbonic anhydrase (CA)-IX, glucose transporter (GLUT)-1, cyclooxygenase (COX)-2, Ki-67, and erythropoietin receptor (EPOR) as immunohistochemical markers for determining the optimal treatment modality for early stage laryngeal carcinoma.

METHODS

Tissue samples from 42 early stage laryngeal carcinomas treated with radiotherapy alone were analyzed immunohistochemically for the expression of 6 markers. The Kaplan-Meier method, univariate and multivariate analyses, and the Cox proportional hazards model were used to analyze the associations between patient and tumor characteristics and immunohistochemical results, and locoregional control.

RESULTS

Increased expression of HIF-1α and CA-IX was significantly correlated with residual tumor; no correlations were observed for the other immunohistochemical markers.

CONCLUSION

High levels of HIF-1α or CA-IX expression were significantly correlated with residual tumor after radiotherapy for early stage laryngeal carcinomas. Alternative treatment modalities to primary radiotherapy should be considered for early stage laryngeal carcinomas showing high HIF-1α or CA-IX expression.

Cyclooxygenase-2 expression is associated with vascular endothelial growth factor-c and lymph node metastasis in human oral tongue cancer

OBJECTIVE

This study aimed to determine the relationship of cyclooxygenase-2 (COX-2) and vascular endothelial growth factor-c (VEGF-C) expression with lymphangiogenesis, lymph node metastasis (LNM), and other clinicopathologic features in human oral tongue cancers.

STUDY DESIGN

Forty tongue cancer specimens were immunohistochemically examined for COX-2 and VEGF-C expression and for lymphatic vessel density (LVD). We analyzed the relationships between COX-2 and VEGF-C expression and the relationships of such expression with clinicopathologic findings and survival of patients.

RESULTS

Eighteen tumors out of 40 (45%) showed COX-2 expression, and 18 tumors (45%) expressed VEGF-C. Twelve tumors (30%) coexpressed COX-2/VEGF-C. A significant correlation was found between COX-2 and VEGF-C expression (P < .01). Of note, COX-2/VEGF-C coexpression significantly correlated with lymphangiogenesis, LNM, TNM stage (P < .01), and LVD (P < .05). In Cox regression for survival, COX-2/VEGF-C coexpression was identified as an independent prognostic factor (P < .05).

CONCLUSIONS

Our results suggest that examination of immunohistochemical expression of COX-2 and VEGF-C predicts LNM and survival in human oral tongue cancers.

Wnt5b promotes the cell motility essential for metastasis of oral squamous cell carcinoma through active Cdc42 and RhoA

The activation of Wnt signaling has been reported in many types of squamous cell carcinoma. In this study, using human oral squamous cell carcinoma (OSCC) cells with different metastatic potential, we investigated the involvement of Wnt signaling in metastasis. Further, we aimed to elucidate the characteristic biological features related to high metastatic potential and to identify new target molecules for the suppression of OSCC lymph node metastasis. We compared SAS-Venus (SAS OSCC cells expressing green fluorescent protein) and SAS-LM8, which is a highly metastatic cell line derived from SAS-Venus by in vivo selection. The SAS-LM8 cell line had greater ability of migration and invasion compared to SAS-Venus. Furthermore, a higher number of filopodia-like protrusive structures were produced in SAS-LM8 cells compared to SAS-Venus cells, and the levels of active Cdc42 and active RhoA protein were higher in SAS-LM8 cells compared to SAS-Venus cells. We did not observe any differences in the expression of Wnt/β-catenin target genes between the two cell lines; however, the mRNA levels of Wnt5b were higher in SAS-LM8 cells compared to SAS-Venus cells. To confirm the involvement of Wnt5b in migration in OSCC cells, we examined the effects of the siRNA-mediated knockdown of Wnt5b in SAS-Venus cells and SAS-LM8 cells. The siRNA treatment significantly inhibited migration and the formation of filopodia-like protrusive structures. Conversely, when stimulated with Wnt5b, the migration and formation of filopodia-like protrusions were significantly enhanced and the levels of active Cdc42 and active RhoA proteins were also increased. These results indicate that Wnt5b is involved in the migration ability of OSCC cells through active Cdc42 and RhoA.

Starfish polysaccharides downregulate metastatic activity through the MAPK signaling pathway in MCF-7 human breast cancer cells

We investigated the effects of starfish (Asterina pectinifera) polysaccharides on metastatic activity in MCF-7 estrogen receptor (ER)-positive human breast cancer cells. In wound healing assay, 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced cell migration was dose-dependently decreased by the starfish polysaccharides (PS). Transcription of aromatase, which catalyzes estrogen synthesis from androgen, was reduced by PS. Also, transcription of TPA-induced cyclooxygenase-2 (COX-2), which enhances breast cancer progression and metastasis via the increase of prostaglandin E2 biosynthesis, was downregulated by the PS in a dose-dependent manner. PS decreased the expression and activity of matrix metalloproteinase (MMP)-9, an important factor in the degradation of basement membrane and extracellular matrix in the metastasis process. In contrast, mRNA expression of tissue inhibitor of matrix metalloproteinase (TIMP)-1, a MMP inhibitor, was increased by 10-120 μg/ml of PS but not that of TIMP-2. We also found that PS reversed the phosphorylations of p38, ERK and JNK but not IκBα and NF-κB. These results demonstrate that PS successfully inhibits PKC-mediated cell migration and metastatic activities in MCF-7 ER-positive human breast cancer cells via downregulation of MMP-9 activity mediated by TIMP-1 upregulation and inhibition of aromatase and COX-2 expression. Also, COX-2 and MMP-9 expressions are attenuated through the inhibition of AP-1 transcription activity via the downregulation of c-Jun expression regulated by p38, ERK and JNK signaling. In conclusion, the present investigation shows that PS may prevent COX-2- and MMP-9-mediated metastatic activities in MCF-7 ER-positive breast cancer cells through the downregulation of MAPK signaling pathways.

Vascular endothelial growth factors signalling in normal human dental pulp: a study of gene and protein expression

In the well-vascularized dental pulp vascular endothelial growth factor A (VEGF-A) is expressed. Vascular endothelial growth factor A is a member of the VEGF family, which includes VEGFs-B, -C, and -D. The latter three have not been investigated in the pulp. Vascular endothelial growth factors C and D are the only ligands for vascular endothelial growth factor receptor (VEGFR)-3, which is usually expressed in lymphatic endothelium. They can also activate VEGFR-2, the main angiogenic receptor. We aimed to study VEGFs signalling in human dental pulp at the gene level and to identify the cellular source for protein expression using immunolabelling. All VEGFs (-A, -B, -C, and -D) were expressed in the pulp and may exert both autocrine and paracrine effects in blood vessels and immune cells found to be equipped with VEGFRs-2 and -3. Lymphatic vessel endothelial hyaluronan receptor-positive macrophages, known to be involved in angiogenesis, were found in the pulp, whereas lymphatic vessels were not detected. Twenty-six of 84 VEGF signalling genes, including VEGFR-3, were expressed at a significantly higher level in the pulp than in the control periodontal ligament. In conclusion, the normal human pulp represents a tissue with relatively high VEGF signalling involving both immune responses and vascular activity.

High expression levels of COX-2 and P300 are associated with unfavorable survival in laryngeal squamous cell carcinoma

In order to provide a basis for clinical treatment decisions, we explored whether there was a correlation between the expression of COX-2 and P300 and clinical factors in a group of patients with laryngeal squamous cell carcinoma (LSCC). A retrospective analysis of clinicopathological data was conducted in 80 patients with LSCC who presented between January 1997 and December 1998. An immunohistochemistry tissue microarray was conducted of 80 surgically resected LSCC and 20 adjacent normal tissue specimens. Survival analysis and Kaplan–Meier curves were used to compare the effects of clinicopathological factors on survival. The Cox model was applied for multivariate analysis. The expression level of COX-2/P300 in LSCC tissues and adjacent normal tissues were 47.5/50.0 versus 0.0/15.0 %. The expression of COX-2 and P300 was correlated with higher T category, N category, clinical staging, histological grade and recurrence (P < 0.05). P300 expression was correlated with COX-2 expression (P < 0.05). Univariate survival analysis showed that P300, COX-2, N category, clinical staging and recurrence factors were closely correlated with unfavorable survival (P < 0.05). Multivariate analysis showed that COX-2 expression, histological grade and recurrence were independent prognostic factors for LSCC. High expression levels of COX-2 and P300 indicated poor survival outcomes for patients with LSCC.