Biomedical subjects

S-C Lin

Publications and source records attributed to S-C Lin.

5 recordsLinked to original sources

PubMed2006

Increase of MMP-13 expression in multi-stage oral carcinogenesis and epigallocatechin-3-gallate suppress MMP-13 expression.

BACKGROUND: Matrix metalloproteinases (MMPs) play pivotal roles in tumor progression. MMP-13 (collagenase-3) digests collagen and other extracellular components. MATERIALS AND METHODS: Reverse transcriptase-polymerase chain reaction (RT-PCR), immunohistochemistry and zymograph were used to study the roles of MMP-13 during the neoplastic process of oral squamous cell carcinoma (OSCC). RESULTS: Increase of MMP-13 mRNA and protein expression in OSCC cell lines relative to cultivated normal oral keratinocytes was found. MMP-13 mRNA expression in OSCC was significantly higher than in non-cancerous match tissue (NCMT) in 36 tissue pairs. Esophageal squamous cell carcinoma also exhibited high MMP-13 mRNA expression. The percentage of OSCC exhibiting strong MMP-13 immunoreactivity was significantly higher than pre-invasive lesion and NCMT. Treatment with >5 microm epigallocatechin-3-gallate (EGCG) to OEC-M1 cells suppressed the expression and activity of MMP-13. CONCLUSION: MMP-13 could be a potential tumor marker for OSCC. The effects of EGCG in tumor inhibition may act partially through the modulation of MMP-13.

Adult↗

PubMed2005

Genetic variants of myeloperoxidase and catechol-O-methyltransferase and breast cancer risk.

This nested case-control study evaluated the role of polymorphisms in the myeloperoxidase (MPO) and catechol-O-methyltransferase (COMT) genes that modulate oxidative stress in breast cancer risk in a Chinese population. Our results demonstrate that the MPO A/A genotype was associated with a reduced risk of breast cancer (odds ratio (OR) 0.64; 95% confidence interval (CI) 0.11-3.76), whereas there was no overall association of COMT genotype with breast cancer. Of note, an elevated breast cancer risk associated with the increasing numbers of high-risk genotypes of MPO and COMT genes was observed in women with a longer duration between menarche and first full-term pregnancy.

Breast Neoplasms↗

PubMed2004

Polymorphism in heme oxygenase-1 (HO-1) promoter is related to the risk of oral squamous cell carcinoma occurring on male areca chewers.

Areca (betel) chewing is associated with the high incidence of oral squamous cell carcinoma (OSCC) and oral submucous fibrosis (OSF) in Asians. Heme oxygenase-1 (HO-1), encoding an oxidative response protein, plays protective roles in cells. A (GT)n microsatellite repeat in HO-1 promoter shows polymorphisms and modulates the level of gene transcription. We examined allelotypic frequencies of (GT)n repeats in 83 controls, 147 OSCC and 71 OSF. All subjects were male areca chewers. Logistic regression was used to adjust the age confounding for odds ratio (OR). (GT)n repeat polymorphism was classified into short (S), medium (M) and long (L) alleles. The adjusted OR in OSCC subjects carrying L allelotype relative to S allelotype was 1.75. Buccal squamous cell carcinoma (BSCC) is the most common OSCC subset in areca chewers. L allelotype implied the risk of BSCC with adjusted OR of 2.05, whereas M allelotype appeared protective for non-BSCC with adjusted OR of 0.49. Our findings indicated that longer (GT)n repeat allele in HO-1 promoter is associated with the risks of areca-related OSCC, while the shorter (GT)n repeat allele may have protective effects for OSCC.

Areca↗

PubMed2004

Effect of mCOUP-TF1 deficiency on the glossopharyngeal and vagal sensory ganglia.

Immunohistochemistry for calcitonin gene-related peptide (CGRP), tyrosine hydroxylase and calbindin D-28k was performed on the glossopharyngeal and vagal ganglia in mCOUP-TFI knockout mice to know the effect of its deficiency on different types of primary sensory neurons. In wild type and heterozygous mice, the glossopharyngeal and vagal ganglia contained abundant CGRP-, tyrosine hydroxylase- and calbindin D-28k-immunoreactive (IR) neurons. In the ganglia of mCOUP-TFI knockout mice, a 38% decrease of CGRP-IR neurons was detected. However, the number of tyrosine hydroxylase- or calbindin D-28k-neurons was not altered by the mCOUP-TFI deficiency. In the tongue of knockout mice, the number of CGRP-IR nerve fibers decreased compared to wild-type and heterozygous mice. The development of CGRP-IR petrosal neurons, which supply innervation of the tongue, may depend on mCOUP-TFI.

Animals↗

PubMed2002

A toxicity testing protocol using a bioluminescent reporter bacterium from activated sludge.

A protocol for production, storage, and use of Shock 1 (Shk1) bioreporter cells for toxicity monitoring in wastewater treatment facilities was developed. Shk1 is a bioluminescent toxicity bioreporter for activated sludge previously constructed by the incorporation of lux genes into an activated sludge microorganism.A number of factors affecting Shk1 growth and bioluminescence were examined including the growth medium, tetracycline concentration, storage conditions, and test media. Based on the results of these experiments, a toxicity testing protocol was developed that involved growth of cultures in nutrient broth with tetracycline, storage of cultures at 4 degrees C, cell activation by reinoculation into nutrient broth, and toxicity testing by cell injection into the test media. Effective use of this approach required standardized time intervals for cell growth, storage, activation and exposure in the test media. Bioluminescence from Shk1 cells was measured in nutrient broth and influent wastewater and activated sludge mixed liquor from a municipal wastewater treatment plant. Using the Shk1 toxicity testing protocol, Zn EC(50) values for bioluminescence in nutrient broth, influent wastewater, and activated sludge mixed liquor were approximately 42, 7, and 32 mg/l, respectively. Zn concentrations as low as 1 mg/l could be detected in influent wastewater. The detection limit in influent wastewater is below the Zn concentrations typically reported to affect the activated sludge process.

Culture Media↗