Potential effects of allyl isothiocyanate on inhibiting cellular proliferation and inducing apoptotic pathway in human cisplatin-resistant oral cancer cells.

BACKGROUND/PURPOSE: Cisplatin-resistant oral cancer is clinically difficult to manage and the dose-dependent toxicities of cisplatin has been widely concerned. Allyl isothiocyanate (AITC), known as mustard oil, is a plant-derived compound abundant in cruciferous vegetables. It is reported to have anti-cancer potential as a natural dietary chemopreventive compound against a variety of cancers, but the effect of AITC on cisplatin-resistant cancer cells is still little-known. METHODS: Human CAL27-cisplatin-resistant oral cancer cells (CAR cells) were examined to investigate the antitumor properties of AITC. 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay, IncuCyte™ S3 cell proliferation assay, 4',6-diamidino-2-phenylindole (DAPI) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining as well as Western blot analysis were deployed. RESULTS: AITC decreased CAR cell viability, induced cell death of CAR cells and inhibited the confluences of cultured CAR cells. When CAR cells were treated with AITC, activation of caspase-3 and caspase-9 by AITC was observed and could be reversed by Z-VAD-fmk (pan-caspase inhibitor). Furthermore, the protein expressions of phosphorylated protein kinase B (p-AKT) and phosphorylated mammalian target of rapamycin (p-mTOR) were suppressed in AITC-treated CAR cells, whereas protein expressions of Bax, cytochrome c, Apaf-1, cleaved caspase-3, and cleaved caspase-9 were upregulated in AITC-treated CAR cells. CONCLUSION: AITC can inhibit Akt/mTOR proliferation signaling and promote mitochondria-dependent apoptotic pathway through AITC-enhanced activities of caspase-3 and caspase-9 in CAR cells.

Arecoline N-Oxide Upregulates Caspase-8 Expression in Oral Hyperplastic Lesions of Mice.

Areca nut is strongly associated with oral squamous cell carcinoma (OSCC) occurrence. Arecoline N-oxide (ANO), a metabolite of the areca alkaloid arecoline, exhibits an oral fibrotic effect in NOD/SCID mice. Caspase-8, a cysteine protease encoded by the CASP8 gene, is a central mediator in the extrinsic apoptotic pathway via death receptors. Deregulation of caspase-8 in OSCC has been reported. This study investigates the regulation of caspase-8 in ANO-induced oral squamous epithelial hyperplasia that represents the initial highly proliferative stage of oral carcinogenesis. CASP8 somatic mutations were identified from whole-exome sequencing of OSCC samples. Immunohistochemical staining showed upregulation of caspase-8 in ANO-induced hyperplasia of both NOD-SCID and C57BL/6 mice. Levels of expression of CASP8, APAF-1, BAX, and BAD increased in ANO-treated DOK cells. Co-localization of increased caspase-8 and PCNA levels was detected in ANO-induced hyperplastic lesions, whereas no co-localization among γ-H2A.X, caspase-3, and upregulated caspase-8 was observed. The findings indicate that upregulation of caspase-8 is involved in cell proliferation rather than apoptosis during the initial stage of ANO-mediated oral tumorigenesis.

Preventive effect of celecoxib use against cancer progression and occurrence of oral squamous cell carcinoma.

Overexpression of cyclooxygenase-2 in oral cancer increases lymph node metastasis and is associated with a poor prognosis. The potential of celecoxib (CXB) use is reported in cancer treatment by inhibiting proliferation through apoptosis, but the effects on the epithelial-mesenchymal transition (EMT) and cancer cell mobility remain unclear. We performed a preclinical study and population-based study to evaluate CXB use in the prevention of oral cancer progression and occurrence. The in-vitro findings showed that CXB is involved in the inhibition of EMT and cell mobility through blocking transcription factors (Slug, Snail and ZEB1), cytoplasmic mediators (focal adhesion kinase (FAK), vimentin and ß-catenin), cell adhesion molecules (cadherins and integrins), and surface receptors (AMFR and EGFR). The murine xenograft model showed a 65% inhibition in tumour growth after a 5-week treatment of CXB compared to placebo. Xenograft tumours in placebo-treated mice displayed a well-to-moderate/moderate differentiated SCC grade, while those from CXB-treated mice were well differentiated. The expression levels of membrane EGFR, and nuclear FAK, Slug and ZEB1 were decreased in the xenograft tumours of CXB-treated mice. A retrospective cohort study showed that increasing the daily dose and medication time of CXB was associated with oral cancer prevention. The findings provide an alternative prevention strategy for oral cancer development with CXB use.

Impact of periodontal treatment on hospitalization for adverse respiratory events in asthmatic adults: A propensity-matched cohort study.

BACKGROUND: Periodontal disease is prevalent in asthmatics, but it is unclear whether periodontal treatment plays a role in adverse respiratory events in these patients. We evaluated risk of hospitalization for adverse respiratory events (acute exacerbation, pneumonia, and acute respiratory failure) and mortality in asthmatic adults with and without periodontal treatment. METHODS: We used National Health Insurance (NHI) claims data of Taiwan to identify 4771 asthmatic adults with periodontal disease who underwent periodontal treatment during 2000-2006. The control group consisted of asthmatic adults without periodontal disease at a 1:1 ratio matched by the propensity score. Both groups were followed up for 5years to estimate the risk of hospitalization for adverse respiratory events and mortality. RESULTS: Compared with controls, the periodontal treatment group had lower overall incidence of hospitalization for adverse respiratory events [5.41 vs. 6.07 per 100 person-years, 95% confidence interval (CI)=0.78-0.92] and intensive care unit admissions (1.14 vs. 1.25 per 100 person-years, 95% CI=0.79-0.99). In addition, the all-cause mortality rate was significantly lower in the periodontal treatment group than in the control group during the follow-up period (1.86 vs. 2.79 per 100 person-years, 95% CI=0.59-0.71). CONCLUSION: Asthmatic adults who underwent periodontal treatment were at lower risk of hospitalization for adverse respiratory events and mortality than those without periodontal disease. Asthmatic adults should adopt more precautionary oral hygiene and ensure that they undergo regular periodontal health checkups.

Risk of Periodontal Disease in Patients With Asthma: A Nationwide Population-Based Retrospective Cohort Study.

BACKGROUND: Studies have reported an association between asthma and oral diseases, including periodontal diseases. The aim of this retrospective study is to investigate risk of periodontal diseases for patients with asthma. METHODS: Using the claims data of National Health Insurance of Taiwan and patients without a history of periodontal diseases, 19,206 asthmatic patients, who were newly diagnosed from 2000 through 2010, were identified. For each case, four comparison individuals without history of asthma and periodontal disease were randomly selected from the general population and frequency matched (categorical matched) by sex, age, and year of diagnosis (n = 76,824). Both cohorts were followed to the end of 2011 to monitor occurrence of periodontal diseases. Adjusted hazard ratios (aHRs) of periodontal disease were estimated using Cox proportional hazards regression analysis. RESULTS: Overall incidence of periodontal diseases was 1.18-fold greater in the asthma cohort than in the comparison cohort (P <0.001). Patients with at least three emergency visits annually had an aHR of 55.9 (95% confidence interval [CI] = 50.6 to 61.7) for periodontal diseases compared with those with a mean of less than one visit. Patients with at least three admissions annually also had a similar aHR (51.8) for periodontal disease. In addition, asthmatic patients on inhaled corticosteroid (ICS) therapy had greater aHRs than non-users (aHR = 1.12; 95% CI = 1.03 to 1.23). CONCLUSIONS: In the studied population, asthmatic patients are at an elevated risk of developing periodontal diseases. The risk is much greater for those with emergency medical demands or hospital admissions and those on ICS treatment.

Periodontal Treatment Reduces Risk of Adverse Respiratory Events in Patients With Chronic Obstructive Pulmonary Disease: A Propensity-Matched Cohort Study.

Treatment of periodontal diseases has been associated with benefit outcomes for patients with chronic obstructive pulmonary disease (COPD). However, no population-based cohort study has been conducted. We evaluated this relationship by retrospective cohort study using a large population data.Using the National Health Insurance claims data of Taiwan, we identified 5562 COPD patients with periodontal diseases who had received periodontal treatment as the treatment group. The comparison group was selected at a 1:1 ratio matched by the propensity score estimated with age, sex, date of COPD diagnosis and periodontal treatment, and comorbidities. Both groups were followed up for 5 years to compare risks of acute exacerbation, pneumonia, and acute respiratory failure.The incidence rates of adverse respiratory events were significantly lower in the treatment group than in the comparison group: 3.79 versus 4.21 per 100 person-years for emergency room visits, 2.75 versus 3.65 per 100 person-years for hospitalizations, and 0.66 versus 0.75 per 100 person-years for intensive care unit admissions. The treatment group also had a 37% reduced risk of deaths (1.81 vs 2.87 per 100 person-years), with an adjusted hazard ratio of 0.57 (95% confidence interval 0.52-0.62).Periodontal treatment for COPD patients could reduce the risk of adverse respiratory events and mortality. The adequate periodontal health care is important for COPD patients with periodontal diseases.

Risk of Periodontal Diseases in Patients With Chronic Obstructive Pulmonary Disease: A Nationwide Population-based Cohort Study.

Several studies have reported an association between chronic obstructive pulmonary disease (COPD) and periodontal diseases. However, a large-scale population-based cohort study was previously absent from the literature. Therefore, we evaluated the risk of periodontal diseases in patients with COPD in a nationwide population.From the National Health Insurance claims data of Taiwan, we identified 22,332 patients with COPD who were newly diagnosed during 2000 to 2010. For each case, two individuals without COPD were randomly selected and frequency matched by age, sex, and diagnosis year. Both groups were followed up till the end of 2011.The overall incidence of periodontal diseases was 1.19-fold greater in the COPD group than in the comparison group (32.2 vs 26.4 per 1000 person-years; 95% confidence interval [CI] 1.15-1.24). Compared with non-COPD patients, the adjusted hazard ratios of patients with COPD increased with the number of emergency room visits (from 1.14 [95% CI 1.10-1.19] to 5.09 [95% CI 4.53-5.72]) and admissions (from 1.15 [95% CI 1.10-1.20] to 3.17 [95% CI 2.81-3.57]). In addition, the adjusted hazard ratios of patients with COPD treated with inhaled corticosteroids (1.22, 95% CI 1.11-1.34) and systemic corticosteroids (1.15, 95% CI 1.07-1.23) were significantly higher than those of patients not treated with corticosteroids.Patient with COPD are at a higher risk of developing periodontal diseases than the general population. Our results also support that the risk of periodontal diseases is proportional to COPD control. In addition, patients who receive corticosteroid treatment are at a higher risk of developing periodontal diseases.

A cloud-based forensics tracking scheme for online social network clients.

In recent years, with significant changes in the communication modes, most users are diverted to cloud-based applications, especially online social networks (OSNs), which applications are mostly hosted on the outside and available to criminals, enabling them to impede criminal investigations and intelligence gathering. In the virtual world, how the Law Enforcement Agency (LEA) identifies the "actual" identity of criminal suspects, and their geolocation in social networks, is a major challenge to current digital investigation. In view of this, this paper proposes a scheme, based on the concepts of IP location and network forensics, which aims to develop forensics tracking on OSNs. According to our empirical analysis, the proposed mechanism can instantly trace the "physical location" of a targeted service resource identifier (SRI), when the target client is using online social network applications (Facebook, Twitter, etc.), and can analyze the probable target client "identity" associatively. To the best of our knowledge, this is the first individualized location method and architecture developed and evaluated in OSNs.

Curcumin-loaded nanoparticles induce apoptotic cell death through regulation of the function of MDR1 and reactive oxygen species in cisplatin-resistant CAR human oral cancer cells.

Curcumin is a polyphenolic compound which possesses anticancer potential. It has been shown to induce cell death in a variety of cancer cells, however, its effect on CAL27­cisplatin-resistant human oral cancer cells (CAR cells) has not been elucidated to date. The low water solubility of curcumin which leads to poor bioavailability, however, has been highlighted as a major limiting factor. In this study, we utilized water-soluble PLGA curcumin nanoparticles (Cur-NPs), and investigated the effects of Cur-NPs on CAR cells. The results showed Cur-NPs induced apoptosis in CAR cells but exhibited low cytotoxicity to normal human gingival fibroblasts (HGFs) and normal human oral keratinocytes (OKs). Cur-NPs triggered DNA concentration, fragmentation and subsequent apoptosis. Compared to untreated CAR cells, a more detectable amount of Calcein-AM accumulation was found inside the treated CAR cells. Cur-NPs suppressed the protein and mRNA expression levels of MDR1. Both the activity and the expression levels of caspase-3 and caspase-9 were elevated in the treated CAR cells. The Cur-NP-triggered apoptosis was blocked by specific inhibitors of pan-caspase (z-VAD-fmk), caspase-3 (z-DEVD-fmk), caspase-9 (z-LEHD-fmk) and antioxidant agent (N-acetylcysteine; NAC). Cur-NPs increased reactive oxygen species (ROS) production, upregulated the protein expression levels of cleaved caspase-3/caspase-9, cytochrome c, Apaf-1, AIF, Bax and downregulated the protein levels of Bcl-2. Our results suggest that Cur-NPs triggered the intrinsic apoptotic pathway through regulating the function of multiple drug resistance protein 1 (MDR1) and the production of reactive oxygen species (ROS) in CAR cells. Cur-NPs could be potentially efficacious in the treatment of cisplatin-resistant human oral cancer.

Epigallocatechin gallate sensitizes CAL-27 human oral squamous cell carcinoma cells to the anti-metastatic effects of gefitinib (Iressa) via synergistic suppression of epidermal growth factor receptor and matrix metalloproteinase-2.

Human head and neck squamous cell carcinoma (HNSCC) is a major cause of cancer-related death during the last decade due to its related metastasis and poor treatment outcomes. Gefitinib (Iressa), a tyrosine kinase inhibitor has been reported to reduce the metastatic abilities of oral cancer. Previous studies have shown that epigallocatechin gallate (EGCG), a green tea polyphenol, possesses cancer chemopreventive and anticancer activity. However, the mechanisms involved in the suppression of invasion and metastasis of human oral cancer cells following co-incubation with gefitinib and EGCG remain poorly understood. In the present study, we attempted to investigate the synergistic effects of a combined treatment of gefitinib and EGCG in CAL-27 cells in vitro and to elucidate the underlying molecular mechanisms associated with the supression of cell migration and invasion. In the present study, we found that the individual treatments or the combined treatment of gefitinib and EGCG synergistically inhibited the invasion and migration of CAL-27 cells using Transwell invasion and wound-healing scratch assays, respectively. Similarly, gefitinib in combination with EGCG synergistically attenuated enzymatic activity and the protein expression of MMP-2 in CAL-27 cells. Furthermore, individual or combined treatment with EGCG and gefitinib suppressed the protein expression of p-EGFR and the phosphorylated protein levels of ERK, JNK, p38 and AKT and displayed inhibitory effects on metastatic ability of CAL-27 cells. Combined effects of EGCG and gefitinib-altered anti-metastatic actions for related gene expression were observed using DNA microarray analysis. Importantly, EGCG sensitizes CAL-27 cells to gefitinib-suppressed phosphorylation of epidermal growth factor receptor (EGFR in vitro. Taken together, our results suggest that the synergistic suppression of the metastatic ability of CAL-27 cells after EGCG and gefitinib individual or combined treatment are mediated through mitogen-activated protein kinase (MAPK) signaling. Our novel findings provide potential insights into the mechanism involved with synergistic responses of gefitinib and EGCG against the progression of oral cancer.

Incidence and clinical significance of zygomaticomaxillary complex fracture involving the temporomandibular joint with emphasis on trismus.

Trismus is frequently a sequel of temporomandibular joint (TMJ) involvement in a zygomaticomaxillary complex (ZMC) fracture. Although trismus is commonly observed in patients with ZMC fracture, continuous follow-up examinations of their degree of mouth opening have rarely been documented. The aim of this retrospective study was to determine the incidence and clinical significance of ZMC fracture involving the glenoid fossa or articular eminence of the TMJ with an emphasis on trismus. The medical and computed tomography (CT) imaging data of 28 patients with ZMC fracture treated by oral and maxillofacial surgeons (OMFSs) (OMFS group) and 174 patients with ZMC fracture treated by surgeons other than OMFSs (non-OMFS group) between May 2002 and May 2006 were reviewed. Maximal interincisal opening (MIO) less than 35 mm or three-finger width was considered limited mouth opening and indicative of trismus. Preoperative CT imaging data indicated that about 64% (18/28) and 50% (87/174) of the patients in the OMFS and non-OMFS groups, respectively, had a ZMC fracture involving the TMJ. Among these OMFS patients, 17 (94.40%) patients had limited mouth opening (MIO range, 7-33 mm) preoperatively, which improved markedly postoperatively. Among the non-OMFS patients with such fractures, 42 (48.3%) patients had trismus preoperatively and two retained trismus postoperatively. Lack of proper preoperative CT images, inadequate postoperative follow-up protocol, and/or neglect by patients and medical staff could influence the outcomes of ZMC fracture involving the TMJ. We make recommendations for reducing the risk of complications subsequent to ZMC fracture involving the TMJ.