Establishment and characterization of an IGSK-2 cell line derived from ascitic fluid of recurrent hCG and somatostatin secreted adenocarcinoma of the stomach

We examined a 32-year-old Japanese man who was clinically diagnosed with gastric cancer, type 4, and histopathologically diagnosed with mucinous and poorly differentiated adenocarcinoma (mucinous > poorly) of the stomach. We successfully established and characterized a cell line (designated as IGSK-2) derived from the ascitic fluid of the patient with recurrent and cisplatin-resistant carcinoma. The IGSK-2 cells grew in multi-layered culture in culture dishes. The cells secreted 18 pg/mL somatostatin, 9.1 mIU/mL human chorionic gonadotrophin (hCG), 8000 U/mL carbohydrate antigen 19-9 and 410 ng/mL carcinoembryonic antigen over 4 days of culture. The population doubling time was approximately 83 h. The susceptibility test of anticancer drugs revealed that IGSK-2 cells were sensitive to Taxol, but were not sensitive to cisplatin, 5-fluorouracil and irinotecan. Immunohistochemical staining revealed that the IGSK-2 cells were positive against antihCG antibody and antiserotonin antibody, and negative against antisomatostatin antibody and antigastrin antibody.