Transformation of benign Barrett's epithelium by repeated acid and bile exposure over 65 weeks: a novel in vitro model.

The mechanism by which gastroesophageal reflux promotes metaplasia→dysplasia→carcinoma is unknown. The aim of the study is to determine if repeated exposure to acid and bile confers a tumorigenic phenotype in a telomerase (hTERT)-immortalized benign Barrett's cell line (BAR-T). BAR-T cells were exposed to acid (pH 4) (A) and bile salt (200 μM glycochenodeoxycholic acid) (B) daily for 5 min up to 65+ weeks.

Mesalamine suppresses the expression of TC22, a novel tropomyosin isoform associated with colonic neoplasia.

Although a protective role for mesalamine against colon cancer in ulcerative colitis has been shown epidemiologically, its molecular mechanism is unknown. We cloned and sequenced a novel human tropomyosin (hTM) isoform, TC22, which is an alternatively spliced variant of normal epithelial hTM isoform 5 (hTM5), identical apart from 25 C-terminal amino acids. TC22 is expressed in 100% of colorectal carcinoma but is not expressed in normal colon epithelial cells.

Bone morphogenetic protein-2-induced transformation involves the activation of mammalian target of rapamycin.

Bone morphogenetic protein-2 (BMP-2) is an evolutionary conserved protein that is essential for embryonic development. BMP-2 is highly expressed in approximately 98% of human lung carcinomas with little expression in normal lung tissues. BMP-2 has been shown to enhance mobility, invasiveness, and metastasis of cancer cell lines.