Serum level of the periostin, a homologue of an insect cell adhesion molecule, as a prognostic marker in nonsmall cell lung carcinomas

BACKGROUND. Periostin protein shares structural and sequence homology with fasciclin I, which is an insect adhesion molecule. Periostin has a typical signal peptide at the N-terminal end, which suggests that it is a secreted protein. Recently, the authors developed a novel sandwich chemiluminescence assay to determine serum concentrations of periostin. METHODS. The authors investigated the serum periostin level in lung carcino ma patients and attempted to determine the influence of serum periostin lev el on clinical outcome for patients with nonsmall cell lung carcinoma (NSCL C) who had undergone surgery between January 1994 and July 1996. Expression of periostin messenger RNA was also examined by in situ RNA hybridization for lung carcinomas. RESULTS. The periostin gene was shown to be highly expressed at the tumor p eriphery of lung carcinoma tissue but not within the tumor by in situ RNA h ybridization. Serum periostin levels were not significantly different betwe en the NSCLC patients (1142.1 +/- 89.2 ng/mL) and the normal control (962.0 +/- 118.6 ng/mL) (P = 0.2985). There was no relation between serum periost in level and gender, stage, bone metastasis, N status, or T status. However , the serum periostin levels of NSCLC patients had decreased significantly by 4 weeks after the resection of the tumor. The NSCLC patients with high p eriostin level (> 962 ng/mL) had significantly poorer survival than the pat ients with normal periostin level (P = 0.0406). Using the Cox proportional hazards regression model, the authors found that stage (P < 0.0001) and ser um periostin level (P = 0.0226) were independent prognostic factors. CONCLUSIONS. The in situ RNA hybridization data from the current study sugg ested that expression of periostin may be involved in tumor invasionand tha t the serum periostin level may serve as a prognostic marker for NSCLC. (C) 2001 American Cancer Society.