Cell Line Established from Ileal and Rectal Carcinoid Tumors

Reference #:

2007-235

Inventors/Contributors

Ricardo V. Lloyd, M.D.

Description

Carcinoids of the intestine are the most common gastrointestinal carcinoid tumors. Therapeutic options to treat patients with these tumors are limited. There are very few ileal carinoid cell lines available for in vitro studies to analyze new drugs that could be effective in treating patients with metastatic tumors. A replication defective recombinant adenovirus with an SV40 early T-antigen insert was used to infect two intestinal carcinoid tumors to create carcinoid cell lines. The cell lines were studied by cell culture, reverse transcription polymerase chain reaction, Western blotting, and immunohistochemistry. Both cell lines expressed SV40 large T antigens and receptors for TGF(Beta)1, TGF(Beta)2, EGFR, and somatostatin receptors. Treatment with TGF(Beta)1 led to growth inhibition and increased apoptosis in the cultured cells. Octreotide inhibited cell growth of both cell lines while stimulating apoptosis. Treatment of the HC45 cells with gefitinib also inhibited cell growth in a concentration-dependant manner. TGF(Beta) treatment stimulated chromogranin A expression while expression of two other granins, chromogranin B and 7Bs, did not change significantly. RNA profiling of cells treated with TGF(Beta)1 showed increased expression of vitamin D3 receptor. This finding was validated by real-time quantitative polymerase chain reaction, Western blotting, and immunohistochemistry. These results indicate that these carcinoid cell lines can be used to study the proliferative and apoptotic mechanisms involved in intestinal carcinoid tumor growth regulation.

Patent Status

None