Does hydatid disease have protective effects against lung cancer? Sule Karadayi • Sulhattin Arslan • Zeynep Sumer • Mustafa Turan • Haldun Sumer • Kursat Karadayi Received: 6 June 2012 / Accepted: 29 April 2013 / Published online: 5 May 2013 Ó Springer Science+Business Media Dordrecht 2013 Abstract We hypothesized that solid tumors rarely occur in patients with hydatid disease. We obtained the serum of 14 patients diagnosed with hydatid disease, the serum of 10 patients who did not have a history of hydatid disease, and the hydatid cyst fluid from six patients. These sera and fluid samples were added at different concentrations to NCI-H209/An1 human lung small cell carcinoma cells and L929 mouse fibroblasts as a control group. Sera of patients with hydatid diseases had cytotoxic effects on NCI-H209/ An1 cells, but they did not have cytotoxic effects on fibroblast cells. Sera from healthy subjects did not have a cytotoxic effect on the tumor cell line or control fibroblasts. Cyst fluid, also, did not have toxic effects on the NCI- H209/An1 cell line, but was toxic to fibroblasts up to a 1:32 dilution. Sera from patients with hydatid disease had cytotoxic effects on human small cell lung cancer cells in vitro. Keywords Lung cancer Á Hydatid disease Á Cell line Á Cytotoxicity Introduction A hydatid cyst is a parasitic disease caused by Echino- coccus granulosus and is common in sheep and cattle rearing regions of the World, mainly Australia, New Zea- land, South Africa, and Mediterranean countries [1]. Solid tumors following hydatid disease are rare in the literature [2]. Lung cancer is the most frequent form of cancer and is the most common cause of death among all cancers [3]. So this study was designed to investigate the rare combination of lung cancer and hydatid diseases. We obtained the serum of 14 patients diagnosed with hydatid disease, the serum of 10 patients who did not have a history of hydatid disease, and the hydatid cyst fluid from six patients. These sera and fluid samples were added at different concentra- tions to NCI-H209/An1 human lung small cell carcinoma cells and L929 mouse fibroblasts as a control group. The viability of cancer cells was evaluated. Materials and methods Cells NCI-H209/An1 human lung small cell carcinoma cells were used and L929 mouse fibroblasts were used as the control group (Anthrax Institute of Turkey). L929 mouse fibroblasts reproduce by adhering to the surface, whereas NCI-H209/An1 human lung small cell carcinoma cells proliferate in suspension. S. Karadayi (&) Department of Thoracic Surgery, Cumhuriyet University School of Medicine, Sivas, Turkey e-mail: sulekaradayi73@yahoo.com S. Arslan Department of Chest Disease, Cumhuriyet University School of Medicine, Sivas, Turkey Z. Sumer Department of Microbiology, Cumhuriyet University School of Medicine, Sivas, Turkey M. Turan Á K. Karadayi Department of General Surgery, Cumhuriyet University School of Medicine, Sivas, Turkey H. Sumer Department of Public Health, Cumhuriyet University School of Medicine, Sivas, Turkey 123 Mol Biol Rep (2013) 40:4701–4704 DOI 10.1007/s11033-013-2565-8