Human Oral Squamous Cell Carcinoma (human + oral_squamous_cell_carcinoma)

Distribution by Scientific Domains

Selected Abstracts

Anticancer effect of photodynamic therapy with hexenyl ester of 5-aminolevulinic acid in oral squamous cell carcinoma

Yeon-Hee Moon MS
Abstract Background. Five-aminolaevulinic acid (ALA) and its derivatives act as precursors of the photosensitizer protoporphyrin IX (PpIX). In this study, the effect of photodynamic therapy (PDT) with hexenyl ester of ALA (ALA-hx) was examined in a human oral squamous cell carcinoma, YD10B cells. Methods. PpIX accumulation and mRNA expression of coproporphyrinogen oxidase (CPO) by ALA and ALA-hx was examined. Cell viability was examined by MTT assay and the molecular mechanism was investigated. Results. The PpIX synthesis and mRNA expression of CPO was much higher in the cells treated with ALA-hx than ALA. At the concentration that PDT with ALA did not affect cell growth, ALA-hx PDT effectively produced reactive oxygen species (ROS) and suppressed cell growth. Growth inhibition by ALA-hx PDT was due to mitochondrial-dependent apoptosis. Conclusion. Our results suggest that ALA-hx PDT effectively induced apoptosis of YD-10B cells and can be considered as a therapeutic alternative for oral cancer. 2009 Wiley Periodicals, Inc. Head Neck, 2010 [source]

Immunohistochemical expression of RANKL, RANK, and OPG in human oral squamous cell carcinoma

Fu-Hsiung Chuang
Background:, The mechanism of oral squamous cell carcinoma (SCC) invading jawbone remains controversial. Interactions between receptor activator of NF-,B (RANK) and its ligand (RANKL) are required for osteoclastogenesis. The binding of RANK and RANKL induces differentiation of osteoclasts, leading to bony destruction. Osteoprotegerin (OPG), a decoy receptor for RANKL, also binds to RANKL by competing with RANK, and this could protect against osseous destruction. Materials and methods:, Immunoexpression of RANKL, RANK, and OPG in 25 cases of human buccal SCCs without bony invasion and 15 cases of gingival SCCs with mandibular bony invasion was investigated. Normal oral mucosa from five individuals without betel-quid chewing or cigarette smoking was used as a control. The scores are designated as percentage of positive staining intensity of staining for each section. Results:, Strong cytoplasmic staining of RANKL proteins is detected in cancer cells of both buccal and gingival SCCs. The same protein is identified in cytoplasm of osteoclasts for all cases involving bony invasion. Strong cytoplasmic staining of RANKL is confined to basal layer for all normal mucosa. A similar staining pattern is noted for RANK protein in all buccal and gingival SCCs. An absence of staining of RANK protein is noted for all normal tissues. Weak to negative cytoplasmic stained OPG protein is present in all buccal and gingival SCCs, but is absent in all normal tissues. Conclusion:, These findings suggest the potential value of the RANK/RANKL/OPG pathway as biomarkers in human oral SCCs. [source]

The relationship of proliferating cell density at the invasive tumour front with prognostic and risk factors in human oral squamous cell carcinoma

Vijay Tumuluri
BACKGROUND:, We hypothesise that the density of proliferating cells at the invasive tumour front (ITF) has a positive relationship with prognostic and risk factors in human oral squamous cell carcinoma (SCC). METHODS:, Tissues from 47 human oral SCC specimens were collected and stained with a monoclonal antibody directed against the Ki-67 antigen using a horseradish peroxidase based two-step immunostaining method. Counting was performed on two parallel sections at the ITF using an image analyser. The Ki-67 labelling index (LI) was determined by measuring the number of nuclei/mm2 of epithelium. RESULTS:, Our results show that the density of proliferating cells is related to clinical staging, with advanced stage of disease having a significantly higher Ki-67 LI compared with early stage of disease (2111 905 vs. 1908 913; P = 0.03). Importantly, this study shows that tumours that have metastasised have a significantly higher Ki-67 LI than tumours where distant metastasis was not detected (3257 650 vs. 1966 881; P < 0.0001). CONCLUSIONS:, Cell proliferation, as measured by the Ki-67 LI at the ITF, has a positive relationship with clinical staging, tumour thickness, smoking status of the patient and alcohol consumption. Further, we suggest that a multicenter study with a large cohort of patients is indicated to fully elucidate whether cell proliferation at the ITF is directly related to patient survival. [source]

Cyclic guanosine monophosphate phosphodiesterase activity in human gingival carcinoma

Giuseppe Spoto
Abstract Background:, Cyclic guanosine monophosphate (cGMP) is an essential second messenger metabolized by phosphodiesterases (PDEs). Objectives:, We looked for a possible correlation of PDE activities in human oral squamous cell carcinoma (OSCC) with and without lymph node metastases. Materials and methods:, The analysis of phosphodiesterase activity and the cGMP assay were done by reverse-phase HPLC on samples of fresh or frozen gingival tissues. Analysis of cGMP was confirmed with the enzyme-linked immunoabsorption assay. Results and conclusions:, cGMP PDE activity was 34.92 7.17 SD, 12.89 4.43 SD, and 35.88 8.76 SD (nmols/mg of protein), respectively, in controls, samples without lymph node involvement (N,), and specimens with lymph node metastases (N+). cGMP values were 1.97 0.63 SD, 3.30 1.47 SD, and 3.49 1.47 SD (nmols/mg of protein). Our data support the hypothesis of a role for cGMP and PDE in the progression of OSCC. [source]

PIK3CA mutation is an oncogenic aberration at advanced stages of oral squamous cell carcinoma

CANCER SCIENCE, Issue 12 2006
Ken-ichi Kozaki
Phosphatidylinositol 3-kinases (PI3K) are a group of heterodimeric lipid kinases that regulate many cellular processes. Gene amplification and somatic mutations mainly within the helical (exon 9) and kinase (exon 20) domains of PIK3CA, which encode the 110-kDa catalytic subunit of PI3K and are mapped to 3q26, have been reported in various human cancers. Herein, 14 human oral squamous cell carcinoma (OSCC) cell lines and 108 primary OSCC tumors were investigated for activating mutations at exons 9 and 20 as well as amplifications in PIK3CA. PIK3CA missense mutations in exons 9 and 20 were identified in 21.4% (3/14) of OSCC cell lines and 7.4% (8/108) of OSCC tumors by genomic DNA sequencing. An increase in the copy number of PIK3CA, although small, was detected in 57.1% (8/14) of OSCC lines and 16.7% (18/108) of OSCC tumors using quantitative real-time PCR. A significant correlation between somatic mutations of PIK3CA and disease stage was observed: the frequency of mutations was higher in stage IV (16.1%, 5/31) than in a subset of early stages (stages I,III) (3.9%, 3/77; P = 0.042, Fisher's extract test). In contrast, the amplification of PIK3CA was observed at a similar frequency among all stages. AKT was highly phosphorylated in OSCC cell lines with PIK3CA mutations compared to those without mutations, despite the amplification. The results suggest that somatic mutations of the PIK3CA gene are likely to occur late in the development of OSCC, and play a crucial role through the PI3K,AKT signaling pathway in cancer progression. (Cancer Sci 2006; 97: 1351,1358) [source]

Antioxidant enzyme levels in oral squamous cell carcinoma and normal human oral epithelium

J. Yang
Abstract Background:, The antioxidant enzymes (manganese- and copper-zinc-containing superoxide dismutases, catalast and glutathione peroxidase) limit cell injury induced by reactive oxygen species. The purpose of the study was to determine whether human oral squamous cell carcinomas have altered antioxidant enzyme levels. This study is the first to undertake this task in human oral mucosa and squamous cell carcinoma. Methods:, Semiquantitative immunohistochemistry was used to examine 26 archived oral squamous cell carcinoma biopsies. Fourteen well-differentiated and 12 poorly differentiated tumors were examined, as were 12 specimens of oral mucosa. All sections were reviewed by two oral and maxillofacial pathologists, and image analysis of the immunostained sections was performed using NIH Image. Antioxidant enzyme staining intensities were compared in the different groups by Duncan's multiple range test. Results:, In general, mucosal basal cells displayed lower antioxidant enzyme levels than spinous cells, and primary tumor cells displayed lower antioxidant enzyme staining intensities than did their normal cell counterparts. Moreover, poorly differentiated tumor cells showed lower antioxidant enzyme staining intensities than well-differentiated tumor cells. Manganese-containing superoxide dismutase staining intensities were, however, higher in well-differentiated oral squamous cell carcinomas than their normal cells of origin. Conclusions:, Detection of antioxidant enzymes may be a useful future marker in the molecular diagnosis of the oral cancer. Moreover, it may be possible to not only monitor the effectiveness of chemopreventitive and therapeutic strategies in oral cancer using these enzymes, but to monitor tumor recurrence. [source]