Novel cytological model for the identification of early oral cancer diagnostic markers: The carcinoma sequence model.

Most oral squamous cell carcinomas (OSCCs) arise from a premalignant lesion, oral epithelial dysplasia; however, useful markers for the early detection of OSCC are lacking. The present study aimed to establish a novel experimental model to observe changes in the sequential expression patterns of mRNAs and proteins in a rat model of tongue cancer using liquid-based cytology techniques. Cytology specimens were collected at 2, 5, 8, 11, 14, 17 and 21 weeks from rats treated with 4-nitroquinoline 1-oxide to induce tongue cancer. The expression of candidate biomarkers was examined by performing immunocytochemistry and reverse transcription-quantitative PCR. The percentage of positively stained nuclei was calculated as the labeling index (LI). All rats developed OSCC of the tongue at 21 weeks. The mRNA expression levels of bromodomain protein 4 (Brd4), c-Myc and Tp53 were upregulated during the progression from negative for intraepithelial lesion or malignancy to squamous cell carcinoma (SCC). Brd4- and c-Myc-LI increased in low-grade squamous intraepithelial lesion, high-grade squamous intraepithelial lesion and SCC specimens. p53-LI was significantly increased in SCC specimens. This novel experimental model allowed the observation of sequential morphological changes and the expression patterns of mRNAs and proteins during carcinogenesis. Combining immunocytochemistry with cytology-based diagnoses may potentially improve the diagnostic accuracy of OSCC.

Loop-mediated isothermal amplification combined with PCR and immunohistochemistry for detecting Porphyromonas gingivalis in periapical periodontitis.

Porphyromonas gingivalis is important in the development of marginal periodontitis. However, the precise role and localization of P. gingivalis in chronic periapical periodontitis remain unclear. Thus, methods that can detect P. gingivalis in formalin-fixed and paraffin-embedded (FFPE) tissue samples are needed. We assessed a technique combining loop-mediated isothermal amplification (LAMP) with PCR (PCR-LAMP) for detection of P. gingivalis, using 110 FFPE tissue samples of chronic apical periodontitis. PCR-LAMP specifically detected P. gingivalis with high sensitivity in FFPE tissue samples, and the sensitivity of the technique was higher than that of PCR or LAMP alone. The results of immunohistochemistry (IHC) confirmed the specificity of PCR-LAMP. IHC showed that P. gingivalis was localized in a granular layer of chronic apical periodontitis, a region that correlated with the localization of macrophages. This is the first study to describe the localization of P. gingivalis in human periapical periodontitis. In conclusion, PCR-LAMP was an effective tool for detecting P. gingivalis in periapical periodontitis. In addition, IHC results improve our understanding of the role of P. gingivalis in the progression of periapical periodontitis. (J Oral Sci 58, 163-169, 2016).

Rapid and Specific Screening Assay for KRAS Oncogene Mutation by a Novel Gene Amplification Method.

BACKGROUND: Epidermal growth factor receptor (EGFR) is a target of molecular therapeutics for colorectal cancer. However, mutation of Kirsten rat sarcoma viral oncogene homolog (KRAS) gene at codons 12 and 13 attenuates the therapeutic effect of anti-EGFR therapies. Therefore, the detection of KRAS gene mutation is important for therapeutic decision-making. MATERIALS AND METHODS: KRAS gene mutation at codons 12 (c.34G>T, c.35G>C, c.35G>A) and 13 (c.38G>A) in six cancer cell lines were investigated. A loop-mediated isothermal amplification-based procedure was developed that employed peptide nucleic acid to suppress amplification of the wild-type allele. RESULTS: This mutation-oriented gene-amplification procedure can amplify the DNA fragment of the KRAS gene with codon 12 and codon 13 mutation within 30 min. Moreover, boiled cells can work as template resources. CONCLUSION: This newly developed procedure can be useful for patient stratification for anti-EGFR therapies.

Whole transcriptome analysis using next-generation sequencing of sterile-cultured Eisenia andrei for immune system research.

Recently, earthworms have become a useful model for research into the immune system, and it is expected that results obtained using this model will shed light on the sophisticated vertebrate immune system and the evolution of the immune response, and additionally help identify new biomolecules with therapeutic applications. However, for earthworms to be used as a genetic model of the invertebrate immune system, basic molecular and genetic resources, such as an expressed sequence tag (EST) database, must be developed for this organism. Next-generation sequencing technologies have generated EST libraries by RNA-seq in many model species. In this study, we used Illumina RNA-sequence technology to perform a comprehensive transcriptome analysis using an RNA sample pooled from sterile-cultured Eisenia andrei. All clean reads were assembled de novo into 41,423 unigenes using the Trinity program. Using this transcriptome data, we performed BLAST analysis against the GenBank non-redundant (NR) database and obtained a total of 12,285 significant BLAST hits. Furthermore, gene ontology (GO) analysis assigned 78 unigenes to 24 immune class GO terms. In addition, we detected a unigene with high similarity to beta-1,3-glucuronyltransferase 1 (GlcAT-P), which mediates a glucuronyl transfer reaction during the biosynthesis of the carbohydrate epitope HNK-1 (human natural killer-1, also known as CD57), a marker of NK cells. The identified transcripts will be used to facilitate future research into the immune system using E. andrei.

Pigmented oral carcinoma in situ: a case report and literature review.

Oral melanotic lesions, including melanin pigmentation, melanocytic nevus, and malignant melanoma, are well-recognized pathologic entities. However, melanocytic proliferation within malignant oral mucosal lesions is not well documented. We report the unusual case of a 53-year-old Japanese man who developed oral carcinoma in situ (CIS) with melanocytic proliferation and melanin pigmentation in the epithelial layer. The patient, a nonsmoker and an opportunistic drinker, presented with a brown tongue lesion. Initial examination found a large brown pigmented area and multiple small white patchy areas on the right tongue border. The pigmentation had an ill-defined border with uneven color distribution. Physical examination found no abnormalities. Ultrasonography did not find a deeply infiltrating lesion. Oral mucosal malignant melanoma in situ was diagnosed, and partial tongue resection was performed. Histopathologic examination found oral pigmented CIS. To the best of our knowledge, this is only the third reported case of oral pigmented CIS.