[Identification of overexpressed genes induced by nitric oxid in human esophageal carcinoma cell line].

Background & Objective: It is possible that some important genes were overexpressed in esophageal carcinoma cells induced by nitric oxid(NO), but it is not yet clear which the genes are. The objective of this study was to separate and identify the overexpressive genes induced by NO in EC109 esophageal carcinoma cell line.

Methods: Overexpression of the genes induced by nitric oxid(NO) in EC109 esophageal carcinoma cell line was determined by using suppression subtractive hybridization(SSH).

Progressive transformation of immortalized esophageal epithelial cells.

Aim: To investigate the progressive transformation of immortal cells of human fetal esophageal epithelium induced by human papillomavirus, and to examine biological criteria of sequential passage of cells, including cellular phenotype, proliferative rate, telomerase, chromosome and tumorigenicity.

Methods: The SHEE cell series consisted of immortalized embryonic esophageal epithelium which was in malignant transformation when cultivated over sixty passages without co-carcinogens. Cells of the 10th, 31st, 60th and 85th passages were present in progressive development after being transfected with HPV.

Identification of differentially expressed proteins between human esophageal immortalized and carcinomatous cell lines by two-dimensional electrophoresis and MALDI-TOF-mass spectrometry.

Aim: To identify the differentially expressed proteins between the human immortalized esophageal epithelial cell line (SHEE) and the malignant transformed esophageal carcinoma cell line (SHEEC), and to explore new ways for studying esophageal carcinoma associated genes.

Methods: SHEE and SHEEC cell lines were used to separate differentially expressed proteins by two-dimensional electrophoresis. The silver-stained 2-D gels was scanned with EDAS290 digital camera system and analyzed with the PDQuest 6.

Immortal phenotype of the esophageal epithelial cells in the process of immortalization.

To search for potential biomarkers used to monitor the process of immortalization, we investigated the relative level of telomerase activity and other immortal phenotypes in the SHEE esophageal epithelial cell line. This human fetal esophageal epithelial cell line, induced by human papilloma virus (HPV) 18 E6E7, was continually propagated over 100 passages. Fourteenth passage cells (SHEE14) were cultured in a flask with a serum-free medium and continually cultured to the 30th passage (SHEE30).

Telomere and telomerase in the initial stage of immortalization of esophageal epithelial cell.

Aim: To search for the biomarker of cellular immortalization, the telomere length, telomerase activity and its subunits in cultured epithelial cells of human fetal esophagus in the process of immortalization.

Methods: The transgenic cell line of human fetal esophageal epithelium (SHEE) was established with E(6)E(7) genes of human papillomavirus (HPV) type 18 in our laboratory. Morphological phenotype of cultured SHEE cells from the 6th to 30th passages, was examined by phase contrast microscopy, the telomere length was assayed by Southern blot method, and the activity of telomerase was analyzed by telomeric repeat amplification protocol (TRAP).