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.

Prognostic value of LYVE-1-positive lymphatic vessel in tongue squamous cell carcinomas.

The density of lymphatic vessels in 52 cases of human tongue squamous cell carcinoma (TSCC) and normal portions was analyzed. TSCC specimens were immunostained with antibodies against lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1) and podoplanin monoclonal antibody (D2-40). The significance of the LYVE-1-positive vessel density (LVD) was calculated in 6 topographic areas and investigated on the basis of specific clinical and histo-pathological parameters. LYVE-1 positivity was more evident in the muscular area than the submucosal area, while small D2-40-positive lymphatic vessels were not demonstrable in muscular endomysium. The LVD in peri-tumoral submucosal and peri-tumoral muscular areas was lower than in normal counterparts (p<0.01). LVD was higher in the tumor invasion front as compared to tumor-associated stroma (p<0.01). Low LVD in invasion front and peri-tumoral submucosal area was significantly related to regional lymph node metastasis (p<0.05 and p<0.01, respectively). The decrease of LYVE-1-positive lymphatic vessels in the invasion front and peri-tumoral submucosal area would seem to predict cervical lymph node metastasis in TSCC.

Detection of fascin and CCR-7 positive mature dendritic cells in oral lichen planus.

BACKGROUND: Dendritic cells (DC) play a crucial role in the pathogenesis of oral lichen planus (OLP) with respect to antigens presented to T cells. We performed immunohistochemical analysis to elucidate the process of activation of DC in OLP. METHODS: Thirty biopsy specimens were obtained from the patients with OLP. The expressions of CD1a, Langerin, S-100, fascin, chemokine receptor-7 (CCR-7), D2-40, cyclooxygenase-2 (COX-2), and microsomal prostaglandin E synthase-1 (mPGES-1) in DC from OLP and disease free control were investigated using specific antibodies. The distribution and number (1 mm(2)) of DC were assessed in the intra-epithelium and the submucosa specimens. Correlation between the number of DC and epithelium thickness was also determined. RESULT: Immature DC (Langerin(+), CD1a(+), and S-100(+)) were identified in the epithelia from OLP patients and control, though the numbers of Langerin(+) and CD1a(+) positive cells were decreased in the OLP samples as compared to the control. Mature DC (fascin(+)) were identified in the submucosa specimens, not found in the epithelium from OLP or control. Double immunostaining revealed DC positive for fascin and CCR-7 in the submucosa, which had migrated into D2-40(+) lymph vessels. Furthermore, keratinocytes expressed both Prostaglandin E(2) (PGE(2)) converting enzymes, COX-2, and mPGES-1, indicating PGE(2) synthesis in the epithelial layer of the OLP specimens. CONCLUSION: Our results indicate that DC change from immature to mature in the epithelium and are then drawn out to the submucosa. We demonstrate that mature DC localized in the submucosa, it consequently migrates into lymph vessels. This maturation process of DC is an important immunopathological feature of OLP.

Anaplastic large cell lymphoma in gingiva: case report and literature review.

We report an unusual case of gingival anaplastic large-cell lymphoma (ALCL) that occurred in a 76-year-old Japanese woman who showed marked gingival swelling in both the maxilla and mandible. Although the patient received caries and periodontal therapy at the outpatient clinic of our dental hospital, the gingival swelling remained and she was referred to the oral surgery department, where a biopsy of the gingiva was performed. The specimens showed proliferation of large atypical and amphophilic epithelioid cells beneath the covering epithelium. Immunohistochemical analysis of the proliferating cells revealed positivity for CD30 and T-cell markers, such as CD45RB, as well as CD45RO antibodies, and they were weakly positive for the granzyme B antibody. In contrast, the tumor cells were negative for all B-cell markers as well as for CD3, CD56, S-100 protein, epithelial membrane antigen, and p80(NPM/ALK) antibodies. Based on the clinical and histopathologic features, the lesion was diagnosed as an ALCL in both the upper and the lower gingiva. This is an extremely rare case, in which a specific subtype of T-cell lymphoma appeared in the oral cavity.

Butyrate inhibits oral cancer cell proliferation and regulates expression of secretory phospholipase A2-X and COX-2.

Although surgical resection is the first choice for oral cancer, the development of new anti-cancer drugs is of great interest. The effect of the histone deacetylation inhibitor, sodium butyrate (NaBu) on oral cancer cell (OCC) HSC-3 and HSC-4 proliferation in vitro was investigated. The synthesis of rate-limiting enzymes such as sPLA2 (-IIA, -V, -X) and COX-2 was examined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot, as well as PGE2 by ELISA. NaBu acted in a concentration-dependent manner. Over 3 mM, it inhibited OCC proliferation, due to increased p21 expression and cell cycle arrest in the G2/M-phase. At low concentration (< or = 1 mM), NaBu showed no effects or enhanced cell proliferation. NaBu also regulated COX-2 and sPLA2-X expression, and augmented PGE2 synthesis in OCC. These results indicate that NaBu is a novel candidate agent for the treatment of oral cancer. The treatment efficacy must be investigated in additional experiments considering NaBu concentration and tumor cell heterogeneity.

Unusual cyst-like lesions in the parapharyngeal space associated with recurrence of tongue carcinoma.

A 54-year-old male presented with the complaint of a painful sore on the left side of his tongue. Our examination found an ulcer 15 x 20 mm in size on the left edge of the tongue, with peripheral indurations. The lesion was diagnosed histopathologically as squamous cell carcinoma (T2N0M0). Consequently, the lesion was surgical removed and radical neck dissection was performed. Four months after the operation, two unusual cyst-like lesions were identified in the parapharyngeal space by CT and MRI. A biopsy specimen revealed recurrent carcinoma with a cyst-like structure. The route of the tumor metastasis into the parapharyngeal space was obscured, but it was speculated that the excessive lymph accumulation was due to a lymphatic occlusion caused by the surgical procedure, proliferation of the metastatic carcinoma, or stagnation and accumulation of tissue fluid caused by parapharyngeal invasion by the recurrent lesion.