Quantitative assessment of early caries lesion activity using novel dye-enhanced fluorescence imaging.

Objectives: This study aimed to evaluate the validity of the dye-enhanced quantitative light-induced fluorescence (DEQLF) method for assessing early enamel caries activity.

Methods: Seventy extracted human teeth with early enamel caries on smooth surfaces were included. Two dentists evaluated the caries activity using the Nyvad system followed by the DEQLF method.

Lesion activity assessment of early caries using dye-enhanced quantitative light-induced fluorescence.

We aimed to determine whether dye-enhanced quantitative light-induced fluorescence (DEQLF), wherein porous structure of caries lesions is stained with a fluorescent dye, could quantitatively distinguish between active and inactive caries. A total of 126 bovine specimens were prepared to artificially simulate caries activity. Active caries were demineralized with 1% carbopol solution for 3 (A3), 5 (A5), and 10 days (A10).

Clinical assessment of an automated fluorescent plaque index scoring with quantitative light-induced fluorescence.

Objective: The aims of this study were to evaluate the clinical applicability of a new fluorescent plaque index scoring (FPI) with the Turesky modified Quigley-Hein plaque index (mQH) and to evaluate its relationship with plaque maturity.

Methods: In total 69 subjects participated in this study. White-light and fluorescent images of anterior teeth were acquired using a Qraycam (AIOBIO, Seoul, Korea).

Diagnosis and management of cracked tooth by quantitative light-induced fluorescence technology.

Introduction: The aim of this case report was to describe the process of diagnosis and treatment of a cracked tooth using quantitative light-induced fluorescence (QLF).

Case Report: A 43-year-old male presented at our dental clinic with a complaint of cold pain in #17 tooth. A routine oral examination with radiography was performed for evaluation of the oral condition and treatment planning.

Evaluation of tooth wear by estimating enamel thickness with quantitative light-induced fluorescence technology.

Background: Various techniques have been suggested to quantitatively assess tooth wear; most have limited clinical application. The first aim of this in vitro study was to estimate the residual enamel thickness of teeth with various degrees of occlusal wear using quantitative light-induced fluorescence (QLF). The second aim was to identify relationships between the fluorescence parameters of QLF and the conventional tooth wear index (TWI) system.

Comparison of fluorescence parameters between three generations of QLF devices for detecting enamel caries in vitro and on smooth surfaces.

Background: This study compared two fluorescence parameters (fluorescence loss [ΔF] and red fluorescence gain [ΔR]) among three generations of quantitative light-induced fluorescence (QLF) systems with the aim of determining the validities of these parameters in the three devices for differentiating the severity of enamel caries.

Methods: Forty-one extracted human premolars and molars with suspected enamel caries were selected. Fluorescence images of all teeth were obtained using first-, second-, and third-generation QLF systems (Inspektor Pro, QLF-D, and Qraycam, respectively).

Caries detection and quantification around stained pits and fissures in occlusal tooth surfaces with fluorescence.

Occlusal discoloration due to staining frequently occurs on the pits and fissures of teeth. Noncariogenic discoloration (non-CD) refers to the attachment of staining chromogens to sound surfaces, whereas cariogenic discoloration (CD) represents the discoloration of porous structures due to bacterial metabolites and mineral loss from the enamel surface. This study evaluated whether it is possible to distinguish between non-CD and CD on stained occlusal surfaces with fluorescence assessed by the quantitative light-induced fluorescence (QLF) technology.

Quantitative light-induced fluorescence technology for quantitative evaluation of tooth wear.

Various technologies used to objectively determine enamel thickness or dentin exposure have been suggested. However, most methods have clinical limitations. This study was conducted to confirm the potential of quantitative light-induced fluorescence (QLF) using autofluorescence intensity of occlusal surfaces of worn teeth according to enamel grinding depth in vitro.

Celecoxib enhances the inhibitory effect of 5-FU on human squamous cell carcinoma proliferation by ROS production.

Objectives: The role of celecoxib in preventing and treating tumors has attracted broad attention in recent years because of its selective and specific inhibition of COX-2 activity. We investigated the inhibitory effects and mechanisms of celecoxib combined with 5-fluorouracil (5-FU) on proliferation of squamous cell carcinoma cells in vivo and in vitro.

Study Design: Animal study and basic research.

5-lipoxygenase mediates docosahexaenoyl ethanolamide and N-arachidonoyl-L-alanine-induced reactive oxygen species production and inhibition of proliferation of head and neck squamous cell carcinoma cells.

Background: Endocannabinoids have recently drawn attention as promising anti-cancer agents. We previously observed that anandamide (AEA), one of the representative endocannabinoids, effectively inhibited the proliferation of head and neck squamous cell carcinoma (HNSCC) cell lines in a receptor-independent manner. In this study, using HNSCC cell lines, we examined the anti-cancer effects and the mechanisms of action of docosahexaenoyl ethanolamide (DHEA) and N-arachidonoyl-L-alanine (NALA), which are polyunsaturated fatty acid (PUFA)-based ethanolamides like AEA.

Activation of K(+) channel by 1-EBIO rescues the head and neck squamous cell carcinoma cells from Ca(2+) ionophore-induced cell death.

Ion channels in carcinoma and their roles in cell proliferation are drawing attention. Intracellular Ca(2+) ([Ca(2+)]i)-dependent signaling affects the fate of cancer cells. Here we investigate the role of Ca(2+)-activated K(+) channel (SK4) in head and neck squamous cell carcinoma cells (HNSCCs) of different cell lines; SNU-1076, OSC-19 and HN5.

Effect of Celecoxib on Survival of Mobile Tongue Cancer.

Aim: The goal of the present study was to evaluate the effects of celecoxib on treatment outcomes of squamous cell carcinoma of the mobile tongue.

Patients And Methods: Among 158 patients who were diagnosed with mobile tongue cancer, 19 received celecoxib during the preoperative, postoperative, or post-recurrence phase. Differences in disease-specific survival (DSS) and recurrence-free survival (RFS) between patients who received celecoxib (study group) and those who did not (control group) were analyzed.

The effect of underwater gait training on balance ability of stroke patients.

[Purpose] The purpose of this study was to investigate the effects of underwater treadmill gait training on the balance ability of stroke patients. [Subjects] Twenty-two patients with stroke were randomly assigned to an underwater treadmill group (n =11) or a control group (n =11). [Methods] Both groups received general rehabilitation for 30 min per session, 5 times per week, over a 4-week period.

Anticancer effects of anandamide on head and neck squamous cell carcinoma cells via the production of receptor-independent reactive oxygen species.

Background: The endocannabinoids, anandamide (AEA) and 2-arachidonoyl glycerol (2-AG), are considered promising potential anticancer agents. In this study, we examined the anticancer effects of AEA and 2-AG in head and neck squamous cell carcinoma (HNSCC) cell lines.

Methods And Results: Our results showed that AEA effectively inhibited proliferation of HNSCC cells whereas 2-AG did not.

Endoplasmic reticulum stress response as a possible mechanism of cyclooxygenase-2-independent anticancer effect of celecoxib.

Background: We investigated whether the endoplasmic reticulum (ER) stress response could be a cyclooxygenase-2 (COX2)-independent mechanism of growth inhibition by celecoxib in a head and neck squamous cell carcinoma (HNSCC) cell line.

Materials And Methods: We performed western blotting and reverse transcription polymerase chain reaction to analyze the expression of ER stress response-associated proteins C/EBP homologous protein (CHOP), glucose-regulated protein (GRP)-78 and X-box binding protein-1 (XBP1), after treatment of celecoxib in the SNU-1041 cell line. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed to determine the change in growth inhibition by celecoxib after inhibition of the ER stress pathway by CHOP small-interfering RNA (siRNA).

The shunting of arachidonic acid metabolism to 5-lipoxygenase and cytochrome p450 epoxygenase antagonizes the anti-cancer effect of cyclooxygenase-2 inhibition in head and neck cancer cells.

Background: It has recently been found that 5-lipoxygenase (5-LO) and cytochrome P450-2J2 (CYP2J2), molecules capable of arachidonic acid (AA) metabolism, might promote cancer cell viability through several mechanisms similar to those of cyclooxygenase-2 (COX-2). We found that not only COX-2 expression, but also the expression of 5-LO and CYP2J2 is up-regulated in head and neck squamous cell carcinoma (HNSCC) cell lines. From these observations, we hypothesized that AA metabolism by 5-LO and/or CYP2J2 may lower the efficacy of anti-cancer effect by COX-2 inhibition.

The influence of cyclooxygenase-1 expression on the efficacy of cyclooxygenase-2 inhibition in head and neck squamous cell carcinoma cell lines.

We have previously observed that cyclooxygenase-2 (COX-2) inhibition blocked the production of vascular endothelial growth factor (VEGF) in some head and neck squamous cell carcinoma (HNSCC) cells. However, as some HNSCC cells showed little response to COX-2 inhibition, although they highly expressed COX-2 and prostaglandin E2, we set out to elucidate what made this difference between them and focused on the possibility of the differential expression of COX-1. In western blotting, we found that COX-1 was expressed in SNU-1041 and SNU-1066, but not in SNU-1076 and PCI-50.

The effects of the stromal cell-derived cyclooxygenase-2 metabolite prostaglandin E2 on the proliferation of colon cancer cells.

It is well known that tumor-surrounding stromal tissues support tumor development through secreting soluble factors such as various cytokines, chemokines, and growth factors. It has also been suggested that tumor-associated fibroblast and immune cells have a high expression of cyclooxygenase-2 (COX-2) and produce and secrete several prostaglandins (PGs) to adjacent cancer tissues. From these findings, we assumed that COX-2 inhibition might have an anticancer effect on cancer cells even without COX-2 expression in COX-2-dependent mechanisms through blocking the effect of stroma-derived PGs.

Celecoxib inhibits cell proliferation through the activation of ERK and p38 MAPK in head and neck squamous cell carcinoma cell lines.

It has been observed that several cyclooxygenase-2 (COX-2) inhibitory chemicals might inhibit proliferation of various cancer cells through COX-2-independent action. We also identified that celecoxib more selectively kills cell lines derived from head and neck squamous cell carcinoma (HNSCC) than its non-cancerous counterparts, irrespective of COX-2 expression. Herein, we investigated whether the regulation of mitogen-activated protein kinases activity might be one of the main mechanisms related to a conspicuous COX-2-independent tumor-killing effect of celecoxib in HNSCC cell lines.

Differential effects between cyclooxygenase-2 inhibitors and siRNA on vascular endothelial growth factor production in head and neck squamous cell carcinoma cell lines.

Background: Several researchers have observed that cyclooxygenase-2 (COX-2) inhibitors display anticancer effects only at higher concentrations than doses that block COX-2 activity in head and neck squamous cell carcinoma (HNSCC) cells.

Methods: To better understand the exact anticancer mechanism of COX-2-inhibitors, we compared the effects of pharmacologic inhibitors to those of small-interfering RNA against COX-2 on cell-growth, vascular endothelial growth factor (VEGF) production, and intracellular signaling in HNSCC cell lines.

Results: We observed in HNSCC cells, that COX-2-siRNA induced an inhibitory effect on intracellular signaling, but unlike the pharmacologic inhibitors, did not affect cell proliferation.

Conditionally replicating adenovirus improves gene replication efficiency and anticancer effect of E1-deleted adenovirus carrying TRAIL in head and neck squamous cell carcinoma.

To overcome the low efficiency of gene therapy, we combined a conditionally replicating adenovirus (CRAd) and an adenoviral vector with a therapeutic gene. CRAd has an oncolytic activity in cancer cells with abnormal Rb activity and helps the replication of therapeutic genes incorporated in the E1-deleted adenovirus. We investigated the anticancer effect of a combination of CRAd and adenovirus carrying tumor necrosis factor-related apoptosis inducing ligand (ad-TRAIL).

Absence of STAT1 disturbs the anticancer effect induced by STAT3 inhibition in head and neck carcinoma cell lines.

The family of signal transducers and activators of transcription (STAT) are transcription factors. Among them, STAT1 is associated with an apoptosis pathway, while STAT3 is associated with tumorigenicity in various cancer cells. In order to investigate the primary roles of STAT1 and STAT3 in head and neck squamous cell carcinoma (HNSCC), we blocked STAT3 with two JAK inhibitors: AG490 (JAK2-STAT3 pathway inhibitor) and JAK total inhibitor.

Presence of HPV type 6 in dysplasia and carcinoma arising from recurrent respiratory papillomatosis.

Background: We collected rare cases of recurrent respiratory papillomatosis (RRP) undergoing malignant transformation. We sought to identify human papillomavirus (HPV) subtypes in areas of papilloma, dysplasia, and carcinoma and investigate the pattern of protein overexpression.

Methods: Three patients whose disease underwent malignant transformation from RRP to carcinoma were subjected to this study.

Association of CD47 with natural killer cell-mediated cytotoxicity of head-and-neck squamous cell carcinoma lines.

Objective: Integrin-associated protein (CD47) binds specifically to the inhibitory receptor signal-regulatory protein. This study was designed to evaluate the role of CD47 in natural killer (NK) cell-mediated cytotoxicity against cancer cells.

Methods: Head-and-neck squamous cell carcinoma (HNSCC) cell lines were analyzed for the expression of CD47 and susceptibility to NK cell-mediated killing.

Nitric oxide upregulates the cyclooxygenase-2 expression through the cAMP-response element in its promoter in several cancer cell lines.

We previously showed that nitric oxide (NO) induces overexpression of cyclooxygenase-2 (COX-2) and production of prostaglandin E(2) in cancer cells. Here, we investigated the mechanisms by which NO induces COX-2 expression in cancer cells. We found that the cAMP-response element (CRE) is a critical factor in NO-induced COX-2 expression in all cells tested.