Screening and identification of proteins interacting with nucleostemin.

Aim: To identify the proteins interacting with nucleostemin (NS), thereby gaining an insight into the function of NS.

Methods: Yeast two-hybrid assay was performed to screen a human placenta cDNA library with the full length of NS as a bait. X-Gal assay and beta-galactosidase filter assay were subsequently conducted to check the positive clones and the gene was identified by DNA sequencing.

Formation of A2143G mutation of 23S rRNA in progression of clarithromycin resistance in Helicobacter pylori 26695.

The aim of this work was to investigate the link between 23S rRNA mutation and clarithromycin (CLR)-resistant Helicobacter pylori (H. pylori). CLR-resistant (CLRr) H.

Antitumor effect of Gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor, combined with cytotoxic agent on murine hepatocellular carcinoma.

Aim: To investigate the inhibitory effect of gefitinib combined with cytotoxic agent cisplatin (CDDP) on hepatocellular carcinoma (HCC).

Methods: Female Kunming mice and H22 hepatocarcinoma cells were used. Gefitinib at daily dose of 100 mg/kg body weight (BW) or lecithin liquid was given by gastrogavage once a day for 5 or 10 successive days.

Genetic polymorphisms of CYP2E1, GSTT1, GSTP1, GSTM1, ALDH2, and ODC and the risk of advanced precancerous gastric lesions in a Chinese population.

There have been few studies of the associations of genetic polymorphisms with precancerous gastric lesions. We conducted a cross-sectional study to compare the prevalences of several genetic polymorphisms in 302 subjects with mild chronic atrophic gastritis with prevalences in 606 subjects with deep intestinal metaplasia or dysplasia. This stratified random sample of 908 subjects was selected and analyzed for genetic polymorphisms from 2,628 individuals who had gastric biopsies with histopathology in 1989 in Linqu County, Shandong Province, China.

Methylation of p16 CpG islands associated with malignant transformation of gastric dysplasia in a population-based study.

Purpose: Inactivation of p16 by aberrant methylation of CpG islands is a frequent event in carcinomas and precancerous lesions of various organs, including the stomach. The aim of this study is to investigate the relationship between p16 methylation and malignant transformation of human gastric dysplasia (DYS) based on follow-up endoscopic screening in a high-risk population.

Experimental Design: Genomic DNA samples were extracted from paraffin blocks of gastric mucosal biopsies that were histopathologically diagnosed as low-grade DYS from patients who developed gastric carcinomas [GCs (n = 21)] and those that did not do so (n = 21) during 5 years of follow-up.

[The effect of IRESSA on H22 mouse hepatocellular carcinoma].

Objective: To investigate the effect of IRESSA (gefitinib, ZD1839) on H22 murine hepatocellular carcinoma.

Methods: Mice bearing H22 hepatocellular carcinoma were randomly divided into oral control group, Normal saline (NS) control group, cisplatin (CDDP) d1-5 group, CDDP d6-10 group, IRESSA group, IRESSA combined with CDDP early (IRESSA + CDDP d1-5) group, and IRESSA combined with CDDP lately (IRESSA + CDDP d6-10) group. IRESSA was given by daily gastrogavage for 10 days (day 1-day 10) at 100 mg/kg in body weight (BW).

[Enhancement of antioxidant capability of cancer patients during chemotherapy by reduced glutathione].

Background & Objective: It is unknown how administration of reduced glutathione (GSH) affects chemotherapy of cancer patients. This study was designed to investigate the effect of GSH on lipid peroxidation, and activities of antioxidant enzyme among cancer patients with chemotherapy.

Methods: Sixty-two cancer patients with chemotherapy were enrolled randomly into AB or BA group in cross-over pattern.

Cisplatin-induced premature senescence with concomitant reduction of gap junctions in human fibroblasts.

To examine the role of gap junctions in cell senescence, the changes of gap junctions in cisplatin-induced premature senescence of primary cultured fibroblasts were studied and compared with the replicative senescent human fibroblasts. Dye transfer assay for gap junction function and immunofluorescent staining for connexin 43 protein distribution were done respectively. Furthermore, cytofluorimetry and DAPI fluorescence staining were performed for cell cycle and apoptosis analysis.

Identification of antigens by monoclonal antibody PD4 and its expression in Escherichia coli.

Aim: To clone and express the antigen of monoclonal antibody (MAb) PD4 for further investigation of its function.

Methods: MGC803 cDNA expression library was constructed and screened with PD4 as probes to clone the antigen. After failed in the library screening, immunoprecipitation and SDS-polyacrylamide gel electrophoresis were applied to purify the antigen for sequence analysis.

p16 hypermethylation during gastric carcinogenesis of Wistar rats by N-methyl-N'-nitro-N-nitrosoguanidine.

Inactivation of the tumor suppressor gene, p16 by CpG hypermethylation is a common event in various tumors including gastric carcinoma. The aim of this study is to investigate if p16 hypermethylation is an early and frequent event in gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). The frequency and timing of p16 hypermethylation during the multistep gastric carcinogenesis in Wistar rats were analyzed in various microdissected gastric lesions.

Hypermethylation of metallothionein-3 CpG island in gastric carcinoma.

The expression of metallothionein (MT)-3 is often markedly reduced in gastric carcinoma (GC). The molecular mechanism of this MT-3 downregulation is unknown. Transcriptional silencing of MT-3 by methylation of CpG island was investigated by nucleotide sequencing and denaturing high performance liquid chromatography (DHPLC) analyses.

Silencing-specific methylation and single nucleotide polymorphism of hMLH1 promoter in gastric carcinomas.

Aim: To investigate CpG methylation and single nucleotide polymorphism (SNP) of a specific promoter region of hMLH1 in primary gastric carcinoma.

Methods: Primary gastric carcinomas (n=80), their corresponding normal mucosal samples, and gastric mucosal biopsies from normal/gastritis control patients (n=54) were used. Hypermethylation at -253 nt and -251 nt in relation with the translational start site and SNP of a silencing specific region (-339 nt-46 nt) in the hMLH1 promoter were analyzed by Bst UI-combined bisulfite assay (COBRA), denaturing high performance liquid chromatogram (DHPLC), and sequencing.

Simultaneous detection of CpG methylation and single nucleotide polymorphism by denaturing high performance liquid chromatography.

We report here a novel method to simultaneously detect CpG methylation and single nucleotide polymorphisms (SNPs) using denaturing high performance liquid chromatography (DHPLC). PCR products of bisulfite-modified CpG islands were separated using DHPLC. BstUI digestion and DNA sequencing were used in confirmation studies.