However, the origin and natural expression of the clinical specimens of lung cancer remain unknown. Annexin A1, an intracellular protein that can bind calcium and phospholipid, have several important functions in cell proliferation, apoptotic regulation, apoptotic VRT752271 mw cell

phagocytosis, and carcinogenesis [2]. Several findings concerning its role in tumorigenesis are controversial. Annexin A1 expression has been shown to be down regulated in several cancers such as esophageal, prostate, breast, and larynx cancers [3, 4]. However, this marker was upregulated in several other cancers such as pancreatic and hepatocellular carcinoma as well as in several types of breast cancers [5, 6]. Heat shock protein 90 (Hsp90) is a highly abundant and evolutionarily conserved protein in eukaryotic cells. Five Hsp90 isoforms have been identified to date, which include the two major cytoplasmic isoforms, namely, Hsp90-alpha and Hsp90-beta [7]. Hsp90-beta is probably involved in long-term cellular adaptation, and higher levels of Hsp90-beta are involved in normal cellular functions, such as the maintenance of the cytoarchitecture, differentiation, and cytoprotection [7]. Hsp90-beta is also upregulated in several cancers, such as breast cancers [8]. However, the study on the expression of Hsp90-beta and its significance with lung cancer is considerably limited compared with Hsp90-alpha. In the current study, we identified the upregulation

of Hsp90-beta and annexin A1 in lung cancer selleck kinase inhibitor cells, and we further investigated the significance of this upregulation in lung cancer and the potential use of Hsp90-beta and annexin A1

as clinical markers for lung cancer. Methods Cell lines and cell culture Human H446 small cell lung cancer (SCLC) cells and large cell lung cancer (LSCC) H520 (squamous cell carcinoma of the lung) cells were obtained from the Cell Biology Department of WZB117 molecular weight Medical School, Lanzhou University, China. Human A549 LAC (adenocarcinoma of the lung) cells were obtained from the Experimental Center, Medical School, Xi’an Jiaotong University. Sixteen HBE cell lines were Erastin in vitro purchased from the Tumor Cells Collection, Academy of Chinese Medical Sciences, Beijing, China. All cell lines were cultured in an RPMI 1640 medium with 10% FBS, 100 units/mL penicillin, and 100 μg/mL streptomycin (Invitrogen). The solution was maintained at 37°C in humidified 5% CO2 and 95% air incubator. Patients Surgical tissue specimens from 96 patients with primary lung cancer who underwent surgical resection of their tumors at the Gansu Provincial Hospital, Lanzhou, Gansu, China and the second affiliated hospital, Xi’an Jiaotong University, Shaanxi, China from January 2004 to December 2010 were obtained for this retrospective study. The study followed institutional review board guidelines. Informed consent was obtained from each patient. None of the subjects received radio/chemotherapy prior to surgery.