• Toxicological Research
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• v.8 no.2
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• pp.317-329
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• 1992

Fifty chemicals are currently classified as human carcinogens based on epidemiologic and animal data. Humans are daily exposed to them from various sources of exposure via inhalation, dermal contact and oral ingestion. To reduce cancer risk to man, these human carcinogens should be appropriately regulated and monitored environmentally or biologically for routine human cancer risk assessment. A number of mathematical risk assessment models have been introduced, but any realistic and relevant model system is not available for humans. A mechanistic process for human cancer risk assessment was comprehensively reviewed and problems were also discussed. Here, a new conceptual approach using epidemiology and biological human monitoring was suggested for the most relevant method to study human cancer risk assessment.

• Journal of Food Hygiene and Safety
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• v.29 no.3
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• pp.248-251
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• 2014

Dryopteris crassirhizoma is one of the naturally occurring substance wood ferns and is known for having anti-inflammatory, antiviral and anthelmintic activities. However, there is less report about its anticancer effect in human cancer cell lines. In the present study, the effect of methanol extract of dryopteris crassirhizoma (MEDC) on apoptosis in human oral cancer cell lines (MC3 and HN22 cells) was investigated. MEDC inhibited cell viability and induced apoptosis. MEDC significantly increased Bak and truncated Bid proteins in MC3 cells and elevated only truncated Bid compared to the control while other Bcl-2 family proteins were not altered. MEDC has anticancer activity by inducing apoptotic cell death through the regulation of either Bak or Bid. These findings suggest that its extract possibly may be used for treating oral cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6109-6113
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• 2012

Background: Oral cancer has become one of the most prevalent cancers worldwide and human Papillomavirus is one of the risk factors for developing oral cancer. For this study HPV18 was chosen as it is one of the high risk HPV types and may lead to carcinogenesis. However, prevalence of HPV18 infection in Oral Squamous Cell Carcinoma in Malaysia remains unclear. Objective: This study aimed to investigate the viral load of HPV18 DNA in OSCC and potentially malignant lesions using saliva samples. Materials and Methods: Genomic DNAs of thirty saliva samples of normal subjects and thirty saliva samples compromised of 16 samples from potentially malignant lesions and 14 of OSCC patients were amplified for HPV18 DNA using a nested polymerase chain reaction analysis. All PCR products were then analyzed using the Bioanalyzer to confirm presence of HPV18 DNA. Result: From thirty patients examined, only one of 30 (3.3%) cases was found to be positive for HPV18 in this study. Conclusion: The finding of this study revealed that there is a low viral detection of HPV18 in Malaysian OSCC by using saliva samples, suggesting that prevalence of HPV18 may not be important in this group of Malaysian OSCC.

• International Journal of Oral Biology
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• v.43 no.2
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• pp.69-76
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• 2018

Oral squamous cell carcinoma (OSCC) is the most common type of oral malignancy. Numerous therapies have been proposed for its cure. Research is continually being conducted to develop new forms of treatment as current therapies are associated with numerous side-effects. Luteolin, a common dietary flavonoid, has been demonstrated to possess strong anti-cancer activity against various human cancer cell lines. Nevertheless, research into luteolin-based anticancer activity against oral cancer remains scarce. Thus, the objective of this study was to assess the effect of luteolin as an anti-cancer agent. After treatment with luteolin, Ca9-22 and CAL-27 oral cancer cells showed condensed nuclei and enhanced apoptotic rate with evidence of mitochondria-mediated apoptosis. Epithelialmesenchymal transition (EMT) is closely related to tumor migration and invasion. Luteolin suppressed cancer cell invasion and migration in the current study. Elevated expression of E-cadherin, an adherens junction protein, was evident in both cell lines after luteolin treatment. Luteolin also significantly inhibited transcription factors (i.e., N-cadherin, Slug, Snail, Twist, and ZEB-1) that regulated expression of tumor suppressors such as E-cadherin based on Western blot analysis and quantitative PCR. Thus, luteolin could induce mitochondrial apoptosis and inhibit cancer cell invasion and migration by suppressing EMT-induced transcription factors.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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• pp.927-932
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• 2016

Bone morphogenetic proteins (BMPs), belonging to the transforming growth factor-${\beta}$ superfamily, regulate many cellular activities including cell migration, differentiation, adhesion, proliferation and apoptosis. Use of recombinant human bone morphogenic protein-2 (rhBMP-2) in oral and maxillofacial surgery has seen a tremendous increase. Due to its role in many cellular pathways, the influence of this protein on carcinogenesis in different organs has been intensively studied over the past decade. BMPs also have been detected to have a role in the development and progression of many tumors, particularly disease-specific bone metastasis. In oral squamous cell carcinoma - the tumor type accounting for more than 90% of head and neck malignancies- aberrations of both BMP expression and associated signaling pathways have a certain relation with the development and progression of the disease by regulating a range of biological functions in the altered cells. In the current review, we discuss the influence of BMPs -especially rhBMP-2- in the development and progression of oral squamous cell carcinoma.

• International Journal of Oral Biology
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• v.45 no.3
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• pp.134-142
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• 2020

Colon cancer is one of the most common malignant tumors, but there are still a few validated biomarkers of colon cancer. Exosome-mediated microRNAs (miRNAs) have been recognized as potential biomarkers in cancers, and miRNAs can regulate a variety of genes. Recently, Fusobacterium nucleatum was discovered in the tissues of human colon cancer patients. Its role in colon cancer was highlighted. F. nucleatum may contribute to the progression of colon cancer through the mechanism of exosome-mediated miRNAs transfer. However, the exosomal miRNAs regulation mechanism by F. nucleatum in colon cancer is not well known. Thus, we performed next-generation sequencing to investigate the overall pattern of exosomal miRNAs expression in the colon cancer cell culture supernatant. We have confirmed the alterations of various exosomal miRNAs. In addition, to investigate the function of exosomal miRNAs, a Kyoto Encyclopedia of Genes and Genomes analysis was performed on the target genes of changed miRNAs. Potential target genes were associated with a variety of signaling pathways, and one of these pathways was related to colorectal cancer. These findings suggested that F. nucleatum can alter exosomal miRNAs released from colorectal cancer cells. Furthermore, exosomal miRNAs altered by F. nucleatum could be potential biomarkers for the diagnosis and therapy of colon cancer.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.6
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• pp.490-495
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• 2011

Introduction: Development of carcinoma on oral tongue may cause bilateral cervical lymph node metastasis, rapid invasion and growth of the cancer cells due to rich blood supply in muscle tissues. It is not only difficult to develop an animal experimental model, but also to proceed follow-up research after the development of such model as the induction of cancer lead to difficulty in taking nutrition for the experimental animals that often causes early death. Materials and Methods: IIn this study, author have transplanted YD-$10B_{mod}$ cells into nude mouse oral tongues with different cells number ($5{\times}10^4$, $5{\times}10^5$, $5{\times}10^6$ cells/mouse) and observed the development aspect of oral tongue cancers. Results: The cancer developed from orthotopic transplantation of YD-$10B_{mod}$ cells into nude mouse oral tongue show invasion and central necrosis of the tumor, similar to the cancers developed human oral tongue cancer. The difference in tumor size and the time of central necrosis development depending on the number of transplanted tumor cells shows the feasibility of extending the survival period of the nude mouse by limiting the transplanted tumor cells to < $5{\times}10^4$ cells/mouse or under per nude mouse. Conclusion: This nude mouse model could be used effectively in developing effective chemotheray agent and establishing an animal experimental model that can be used to study the mechanism of cervical lymph node metastasis of the oral tongue cancer.

• International Journal of Oral Biology
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• v.44 no.3
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• pp.81-88
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• 2019

Trifolium pratense leaves (red clover) has been used in Oriental and European folk medicine for the treatment of whooping cough, asthma, and eczema, and is now being used to treat and alleviate the symptoms, such as hot flushes, cardiovascular health effects that occur in postmenopausal women. However, relatively little scientific data is available on the physiological activity of this plant. Therefore, in this study, we investigated the anti-cancer activity of T. pratense leaves using methanol extract of T. pratense leaves (MeTP) on human FaDu hypopharyngeal squamous carcinoma cells. MeTP inhibited the viability of FaDu cells by inducing apoptosis through the cleavage of procaspase-3, -7, and -9 and poly (adenosine diphosphate ribose-ribose) polymerase (PARP), downregulation of Bcl-2, and upregulation of Bax, as determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Live & dead assay, 4'6-diamidino-2-phenylindole stain, fluorescence-activated cell sorting analysis, and Western blot analysis. In addition, colony formation was slightly inhibited when FaDu cells were treated with a non-cytotoxic concentration (0.125 mg/mL) of MeTP and almost completely inhibited when cells were treated with 0.25 mg/mL MeTP. Collectively, these results indicate that MeTP induced cell apoptosis via caspase- and mitochondrial-dependent apoptotic pathways, and inhibited colony formation of cancer cells in FaDu human hypopharyngeal squamous carcinoma cells. These findings suggest MeTP should be considered for clinical development as a chemotherapeutic option in oral cancer.

• Biomolecules & Therapeutics
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• v.27 no.1
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• pp.54-62
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• 2019

Cis-3-O-p-hydroxycinnamoyl ursolic acid (HCUA), a triterpenoid compound, was purified from Elaeagnus oldhamii Maxim. This traditional medicinal plant has been used for treating rheumatoid arthritis and lung disorders as well as for its anti-inflammation and anticancer activities. This study aimed to investigate the anti-proliferative and apoptotic-inducing activities of HCUA in oral cancer cells. HCUA exhibited anti-proliferative activity in oral cancer cell lines (Ca9-22 and SAS cells), but not in normal oral fibroblasts. The inhibitory concentration of HCUA that resulted in 50% viability was $24.0{\mu}M$ and $17.8{\mu}M$ for Ca9-22 and SAS cells, respectively. Moreover, HCUA increased the number of cells in the sub-G1 arrest phase and apoptosis in a concentration-dependent manner in both oral cancer cell lines, but not in normal oral fibroblasts. Importantly, HCUA induced p53-mediated transcriptional regulation of pro-apoptotic proteins (Bax, Bak, Bim, Noxa, and PUMA), which are associated with mitochondrial apoptosis in oral cancer cells via the loss of mitochondrial membrane potential. HCUA triggered the production of intracellular reactive oxygen species (ROS) that was ascertained to be involved in HCUA-induced apoptosis by the ROS inhibitors YCG063 and N-acetyl-L-cysteine. As a result, HCUA had potential antitumor activity to oral cancer cells through eliciting ROS-dependent and p53-mediated mitochondrial apoptosis. Overall, HCUA could be applicable for the development of anticancer agents against human oral cancer.

• Journal of dental hygiene science
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• v.19 no.2
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• pp.77-85
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• 2019

In the past gut microbiome has been the main focus of microbiome research. Studies about the microbiome inside oral cavities and other organs are underway. Studies about the relationship between noninfectious diseases and periodontal diseases, and the negative effects of harmful oral microbes on systemic health have been published in the recent past. A lot of attention is being paid towards fostering a healthy oral microbial ecosystem. This study aimed to understand the roles and effects of the microbiome inside the human body can potentially help cure various diseases including inflammatory bowel diseases with no known cure such as Crohn's disease, atopic dermatitis, obesity, cancer, diabetes, brain diseases and oral diseases. The present study examined technological trends in the correlation between the human microbiome and diseases in the human body, interactions between the human body's immunity, the metabolic system, and the microbiome, and research trends in other countries. While it has been proven that human microbiome is closely correlated with human diseases, most studies are still in the early stage of trying to compare the composition of microbiomes between health and patient groups. Since the oral environment is a dynamic environment that changes due to not only food intake but also other external factors such as lifestyle, hygiene, and drug intake, it is necessary to continue in-depth research on the microbiome composition characteristics to understand the complex functions of oral microorganisms. Analyzing the oral microbiome using computational technology may aid in disease diagnosis and prevention.